| /* | 
 |  * This file includes functions to transform a concrete syntax tree (CST) to | 
 |  * an abstract syntax tree (AST).  The main function is PyAST_FromNode(). | 
 |  * | 
 |  */ | 
 | #include "Python.h" | 
 | #include "Python-ast.h" | 
 | #include "grammar.h" | 
 | #include "node.h" | 
 | #include "pyarena.h" | 
 | #include "ast.h" | 
 | #include "token.h" | 
 | #include "parsetok.h" | 
 | #include "graminit.h" | 
 |  | 
 | #include <assert.h> | 
 |  | 
 | /* Data structure used internally */ | 
 | struct compiling { | 
 |     char *c_encoding; /* source encoding */ | 
 |     PyArena *c_arena; /* arena for allocating memeory */ | 
 |     const char *c_filename; /* filename */ | 
 | }; | 
 |  | 
 | static asdl_seq *seq_for_testlist(struct compiling *, const node *); | 
 | static expr_ty ast_for_expr(struct compiling *, const node *); | 
 | static stmt_ty ast_for_stmt(struct compiling *, const node *); | 
 | static asdl_seq *ast_for_suite(struct compiling *, const node *); | 
 | static asdl_seq *ast_for_exprlist(struct compiling *, const node *, | 
 |                                   expr_context_ty); | 
 | static expr_ty ast_for_testlist(struct compiling *, const node *); | 
 | static stmt_ty ast_for_classdef(struct compiling *, const node *, asdl_seq *); | 
 |  | 
 | /* Note different signature for ast_for_call */ | 
 | static expr_ty ast_for_call(struct compiling *, const node *, expr_ty); | 
 |  | 
 | static PyObject *parsenumber(struct compiling *, const char *); | 
 | static PyObject *parsestr(struct compiling *, const node *n, int *bytesmode); | 
 | static PyObject *parsestrplus(struct compiling *, const node *n, | 
 |                               int *bytesmode); | 
 |  | 
 | #ifndef LINENO | 
 | #define LINENO(n)       ((n)->n_lineno) | 
 | #endif | 
 |  | 
 | #define COMP_GENEXP   0 | 
 | #define COMP_LISTCOMP 1 | 
 | #define COMP_SETCOMP  2 | 
 |  | 
 | static identifier | 
 | new_identifier(const char* n, PyArena *arena) | 
 | { | 
 |     PyObject* id = PyUnicode_DecodeUTF8(n, strlen(n), NULL); | 
 |     Py_UNICODE *u; | 
 |     if (!id) | 
 |         return NULL; | 
 |     u = PyUnicode_AS_UNICODE(id); | 
 |     /* Check whether there are non-ASCII characters in the | 
 |        identifier; if so, normalize to NFKC. */ | 
 |     for (; *u; u++) { | 
 |         if (*u >= 128) { | 
 |             PyObject *m = PyImport_ImportModuleNoBlock("unicodedata"); | 
 |             PyObject *id2; | 
 |             if (!m) | 
 |                 return NULL; | 
 |             id2 = PyObject_CallMethod(m, "normalize", "sO", "NFKC", id); | 
 |             Py_DECREF(m); | 
 |             if (!id2) | 
 |                 return NULL; | 
 |             Py_DECREF(id); | 
 |             id = id2; | 
 |             break; | 
 |         } | 
 |     } | 
 |     PyUnicode_InternInPlace(&id); | 
 |     PyArena_AddPyObject(arena, id); | 
 |     return id; | 
 | } | 
 |  | 
 | #define NEW_IDENTIFIER(n) new_identifier(STR(n), c->c_arena) | 
 |  | 
 | /* This routine provides an invalid object for the syntax error. | 
 |    The outermost routine must unpack this error and create the | 
 |    proper object.  We do this so that we don't have to pass | 
 |    the filename to everything function. | 
 |  | 
 |    XXX Maybe we should just pass the filename... | 
 | */ | 
 |  | 
 | static int | 
 | ast_error(const node *n, const char *errstr) | 
 | { | 
 |     PyObject *u = Py_BuildValue("zi", errstr, LINENO(n)); | 
 |     if (!u) | 
 |         return 0; | 
 |     PyErr_SetObject(PyExc_SyntaxError, u); | 
 |     Py_DECREF(u); | 
 |     return 0; | 
 | } | 
 |  | 
 | static void | 
 | ast_error_finish(const char *filename) | 
 | { | 
 |     PyObject *type, *value, *tback, *errstr, *loc, *tmp; | 
 |     long lineno; | 
 |  | 
 |     assert(PyErr_Occurred()); | 
 |     if (!PyErr_ExceptionMatches(PyExc_SyntaxError)) | 
 |         return; | 
 |  | 
 |     PyErr_Fetch(&type, &value, &tback); | 
 |     errstr = PyTuple_GetItem(value, 0); | 
 |     if (!errstr) | 
 |         return; | 
 |     Py_INCREF(errstr); | 
 |     lineno = PyLong_AsLong(PyTuple_GetItem(value, 1)); | 
 |     if (lineno == -1) { | 
 |         Py_DECREF(errstr); | 
 |         return; | 
 |     } | 
 |     Py_DECREF(value); | 
 |  | 
 |     loc = PyErr_ProgramText(filename, lineno); | 
 |     if (!loc) { | 
 |         Py_INCREF(Py_None); | 
 |         loc = Py_None; | 
 |     } | 
 |     tmp = Py_BuildValue("(zlOO)", filename, lineno, Py_None, loc); | 
 |     Py_DECREF(loc); | 
 |     if (!tmp) { | 
 |         Py_DECREF(errstr); | 
 |         return; | 
 |     } | 
 |     value = PyTuple_Pack(2, errstr, tmp); | 
 |     Py_DECREF(errstr); | 
 |     Py_DECREF(tmp); | 
 |     if (!value) | 
 |         return; | 
 |     PyErr_Restore(type, value, tback); | 
 | } | 
 |  | 
 | /* num_stmts() returns number of contained statements. | 
 |  | 
 |    Use this routine to determine how big a sequence is needed for | 
 |    the statements in a parse tree.  Its raison d'etre is this bit of | 
 |    grammar: | 
 |  | 
 |    stmt: simple_stmt | compound_stmt | 
 |    simple_stmt: small_stmt (';' small_stmt)* [';'] NEWLINE | 
 |  | 
 |    A simple_stmt can contain multiple small_stmt elements joined | 
 |    by semicolons.  If the arg is a simple_stmt, the number of | 
 |    small_stmt elements is returned. | 
 | */ | 
 |  | 
 | static int | 
 | num_stmts(const node *n) | 
 | { | 
 |     int i, l; | 
 |     node *ch; | 
 |  | 
 |     switch (TYPE(n)) { | 
 |         case single_input: | 
 |             if (TYPE(CHILD(n, 0)) == NEWLINE) | 
 |                 return 0; | 
 |             else | 
 |                 return num_stmts(CHILD(n, 0)); | 
 |         case file_input: | 
 |             l = 0; | 
 |             for (i = 0; i < NCH(n); i++) { | 
 |                 ch = CHILD(n, i); | 
 |                 if (TYPE(ch) == stmt) | 
 |                     l += num_stmts(ch); | 
 |             } | 
 |             return l; | 
 |         case stmt: | 
 |             return num_stmts(CHILD(n, 0)); | 
 |         case compound_stmt: | 
 |             return 1; | 
 |         case simple_stmt: | 
 |             return NCH(n) / 2; /* Divide by 2 to remove count of semi-colons */ | 
 |         case suite: | 
 |             if (NCH(n) == 1) | 
 |                 return num_stmts(CHILD(n, 0)); | 
 |             else { | 
 |                 l = 0; | 
 |                 for (i = 2; i < (NCH(n) - 1); i++) | 
 |                     l += num_stmts(CHILD(n, i)); | 
 |                 return l; | 
 |             } | 
 |         default: { | 
 |             char buf[128]; | 
 |  | 
 |             sprintf(buf, "Non-statement found: %d %d", | 
 |                     TYPE(n), NCH(n)); | 
 |             Py_FatalError(buf); | 
 |         } | 
 |     } | 
 |     assert(0); | 
 |     return 0; | 
 | } | 
 |  | 
 | /* Transform the CST rooted at node * to the appropriate AST | 
 | */ | 
 |  | 
 | mod_ty | 
 | PyAST_FromNode(const node *n, PyCompilerFlags *flags, const char *filename, | 
 |                PyArena *arena) | 
 | { | 
 |     int i, j, k, num; | 
 |     asdl_seq *stmts = NULL; | 
 |     stmt_ty s; | 
 |     node *ch; | 
 |     struct compiling c; | 
 |  | 
 |     if (flags && flags->cf_flags & PyCF_SOURCE_IS_UTF8) { | 
 |         c.c_encoding = "utf-8"; | 
 |         if (TYPE(n) == encoding_decl) { | 
 | #if 0 | 
 |             ast_error(n, "encoding declaration in Unicode string"); | 
 |             goto error; | 
 | #endif | 
 |             n = CHILD(n, 0); | 
 |         } | 
 |     } else if (TYPE(n) == encoding_decl) { | 
 |         c.c_encoding = STR(n); | 
 |         n = CHILD(n, 0); | 
 |     } else { | 
 |         /* PEP 3120 */ | 
 |         c.c_encoding = "utf-8"; | 
 |     } | 
 |     c.c_arena = arena; | 
 |     c.c_filename = filename; | 
 |  | 
 |     k = 0; | 
 |     switch (TYPE(n)) { | 
 |         case file_input: | 
 |             stmts = asdl_seq_new(num_stmts(n), arena); | 
 |             if (!stmts) | 
 |                 return NULL; | 
 |             for (i = 0; i < NCH(n) - 1; i++) { | 
 |                 ch = CHILD(n, i); | 
 |                 if (TYPE(ch) == NEWLINE) | 
 |                     continue; | 
 |                 REQ(ch, stmt); | 
 |                 num = num_stmts(ch); | 
 |                 if (num == 1) { | 
 |                     s = ast_for_stmt(&c, ch); | 
 |                     if (!s) | 
 |                         goto error; | 
 |                     asdl_seq_SET(stmts, k++, s); | 
 |                 } | 
 |                 else { | 
 |                     ch = CHILD(ch, 0); | 
 |                     REQ(ch, simple_stmt); | 
 |                     for (j = 0; j < num; j++) { | 
 |                         s = ast_for_stmt(&c, CHILD(ch, j * 2)); | 
 |                         if (!s) | 
 |                             goto error; | 
 |                         asdl_seq_SET(stmts, k++, s); | 
 |                     } | 
 |                 } | 
 |             } | 
 |             return Module(stmts, arena); | 
 |         case eval_input: { | 
 |             expr_ty testlist_ast; | 
 |  | 
 |             /* XXX Why not comp_for here? */ | 
 |             testlist_ast = ast_for_testlist(&c, CHILD(n, 0)); | 
 |             if (!testlist_ast) | 
 |                 goto error; | 
 |             return Expression(testlist_ast, arena); | 
 |         } | 
 |         case single_input: | 
 |             if (TYPE(CHILD(n, 0)) == NEWLINE) { | 
 |                 stmts = asdl_seq_new(1, arena); | 
 |                 if (!stmts) | 
 |                     goto error; | 
 |                 asdl_seq_SET(stmts, 0, Pass(n->n_lineno, n->n_col_offset, | 
 |                                             arena)); | 
 |                 if (!asdl_seq_GET(stmts, 0)) | 
 |                     goto error; | 
 |                 return Interactive(stmts, arena); | 
 |             } | 
 |             else { | 
 |                 n = CHILD(n, 0); | 
 |                 num = num_stmts(n); | 
 |                 stmts = asdl_seq_new(num, arena); | 
 |                 if (!stmts) | 
 |                     goto error; | 
 |                 if (num == 1) { | 
 |                     s = ast_for_stmt(&c, n); | 
 |                     if (!s) | 
 |                         goto error; | 
 |                     asdl_seq_SET(stmts, 0, s); | 
 |                 } | 
 |                 else { | 
 |                     /* Only a simple_stmt can contain multiple statements. */ | 
 |                     REQ(n, simple_stmt); | 
 |                     for (i = 0; i < NCH(n); i += 2) { | 
 |                         if (TYPE(CHILD(n, i)) == NEWLINE) | 
 |                             break; | 
 |                         s = ast_for_stmt(&c, CHILD(n, i)); | 
 |                         if (!s) | 
 |                             goto error; | 
 |                         asdl_seq_SET(stmts, i / 2, s); | 
 |                     } | 
 |                 } | 
 |  | 
 |                 return Interactive(stmts, arena); | 
 |             } | 
 |         default: | 
 |             PyErr_Format(PyExc_SystemError, | 
 |                          "invalid node %d for PyAST_FromNode", TYPE(n)); | 
 |             goto error; | 
 |     } | 
 |  error: | 
 |     ast_error_finish(filename); | 
 |     return NULL; | 
 | } | 
 |  | 
 | /* Return the AST repr. of the operator represented as syntax (|, ^, etc.) | 
 | */ | 
 |  | 
 | static operator_ty | 
 | get_operator(const node *n) | 
 | { | 
 |     switch (TYPE(n)) { | 
 |         case VBAR: | 
 |             return BitOr; | 
 |         case CIRCUMFLEX: | 
 |             return BitXor; | 
 |         case AMPER: | 
 |             return BitAnd; | 
 |         case LEFTSHIFT: | 
 |             return LShift; | 
 |         case RIGHTSHIFT: | 
 |             return RShift; | 
 |         case PLUS: | 
 |             return Add; | 
 |         case MINUS: | 
 |             return Sub; | 
 |         case STAR: | 
 |             return Mult; | 
 |         case SLASH: | 
 |             return Div; | 
 |         case DOUBLESLASH: | 
 |             return FloorDiv; | 
 |         case PERCENT: | 
 |             return Mod; | 
 |         default: | 
 |             return (operator_ty)0; | 
 |     } | 
 | } | 
 |  | 
 | static const char* FORBIDDEN[] = { | 
 |     "None", | 
 |     "True", | 
 |     "False", | 
 |     NULL, | 
 | }; | 
 |  | 
 | static int | 
 | forbidden_name(identifier name, const node *n, int full_checks) | 
 | { | 
 |     assert(PyUnicode_Check(name)); | 
 |     if (PyUnicode_CompareWithASCIIString(name, "__debug__") == 0) { | 
 |         ast_error(n, "assignment to keyword"); | 
 |         return 1; | 
 |     } | 
 |     if (full_checks) { | 
 |         const char **p; | 
 |         for (p = FORBIDDEN; *p; p++) { | 
 |             if (PyUnicode_CompareWithASCIIString(name, *p) == 0) { | 
 |                 ast_error(n, "assignment to keyword"); | 
 |                 return 1; | 
 |             } | 
 |         } | 
 |     } | 
 |     return 0; | 
 | } | 
 |  | 
 | /* Set the context ctx for expr_ty e, recursively traversing e. | 
 |  | 
 |    Only sets context for expr kinds that "can appear in assignment context" | 
 |    (according to ../Parser/Python.asdl).  For other expr kinds, it sets | 
 |    an appropriate syntax error and returns false. | 
 | */ | 
 |  | 
 | static int | 
 | set_context(struct compiling *c, expr_ty e, expr_context_ty ctx, const node *n) | 
 | { | 
 |     asdl_seq *s = NULL; | 
 |     /* If a particular expression type can't be used for assign / delete, | 
 |        set expr_name to its name and an error message will be generated. | 
 |     */ | 
 |     const char* expr_name = NULL; | 
 |  | 
 |     /* The ast defines augmented store and load contexts, but the | 
 |        implementation here doesn't actually use them.  The code may be | 
 |        a little more complex than necessary as a result.  It also means | 
 |        that expressions in an augmented assignment have a Store context. | 
 |        Consider restructuring so that augmented assignment uses | 
 |        set_context(), too. | 
 |     */ | 
 |     assert(ctx != AugStore && ctx != AugLoad); | 
 |  | 
 |     switch (e->kind) { | 
 |         case Attribute_kind: | 
 |             e->v.Attribute.ctx = ctx; | 
 |             if (ctx == Store && forbidden_name(e->v.Attribute.attr, n, 1)) | 
 |                 return 0; | 
 |             break; | 
 |         case Subscript_kind: | 
 |             e->v.Subscript.ctx = ctx; | 
 |             break; | 
 |         case Starred_kind: | 
 |             e->v.Starred.ctx = ctx; | 
 |             if (!set_context(c, e->v.Starred.value, ctx, n)) | 
 |                 return 0; | 
 |             break; | 
 |         case Name_kind: | 
 |             if (ctx == Store) { | 
 |                 if (forbidden_name(e->v.Name.id, n, 1)) | 
 |                     return 0; /* forbidden_name() calls ast_error() */ | 
 |             } | 
 |             e->v.Name.ctx = ctx; | 
 |             break; | 
 |         case List_kind: | 
 |             e->v.List.ctx = ctx; | 
 |             s = e->v.List.elts; | 
 |             break; | 
 |         case Tuple_kind: | 
 |             if (asdl_seq_LEN(e->v.Tuple.elts))  { | 
 |                 e->v.Tuple.ctx = ctx; | 
 |                 s = e->v.Tuple.elts; | 
 |             } | 
 |             else { | 
 |                 expr_name = "()"; | 
 |             } | 
 |             break; | 
 |         case Lambda_kind: | 
 |             expr_name = "lambda"; | 
 |             break; | 
 |         case Call_kind: | 
 |             expr_name = "function call"; | 
 |             break; | 
 |         case BoolOp_kind: | 
 |         case BinOp_kind: | 
 |         case UnaryOp_kind: | 
 |             expr_name = "operator"; | 
 |             break; | 
 |         case GeneratorExp_kind: | 
 |             expr_name = "generator expression"; | 
 |             break; | 
 |         case Yield_kind: | 
 |             expr_name = "yield expression"; | 
 |             break; | 
 |         case ListComp_kind: | 
 |             expr_name = "list comprehension"; | 
 |             break; | 
 |         case SetComp_kind: | 
 |             expr_name = "set comprehension"; | 
 |             break; | 
 |         case DictComp_kind: | 
 |             expr_name = "dict comprehension"; | 
 |             break; | 
 |         case Dict_kind: | 
 |         case Set_kind: | 
 |         case Num_kind: | 
 |         case Str_kind: | 
 |             expr_name = "literal"; | 
 |             break; | 
 |         case Ellipsis_kind: | 
 |             expr_name = "Ellipsis"; | 
 |             break; | 
 |         case Compare_kind: | 
 |             expr_name = "comparison"; | 
 |             break; | 
 |         case IfExp_kind: | 
 |             expr_name = "conditional expression"; | 
 |             break; | 
 |         default: | 
 |             PyErr_Format(PyExc_SystemError, | 
 |                          "unexpected expression in assignment %d (line %d)", | 
 |                          e->kind, e->lineno); | 
 |             return 0; | 
 |     } | 
 |     /* Check for error string set by switch */ | 
 |     if (expr_name) { | 
 |         char buf[300]; | 
 |         PyOS_snprintf(buf, sizeof(buf), | 
 |                       "can't %s %s", | 
 |                       ctx == Store ? "assign to" : "delete", | 
 |                       expr_name); | 
 |         return ast_error(n, buf); | 
 |     } | 
 |  | 
 |     /* If the LHS is a list or tuple, we need to set the assignment | 
 |        context for all the contained elements. | 
 |     */ | 
 |     if (s) { | 
 |         int i; | 
 |  | 
 |         for (i = 0; i < asdl_seq_LEN(s); i++) { | 
 |             if (!set_context(c, (expr_ty)asdl_seq_GET(s, i), ctx, n)) | 
 |                 return 0; | 
 |         } | 
 |     } | 
 |     return 1; | 
 | } | 
 |  | 
 | static operator_ty | 
 | ast_for_augassign(struct compiling *c, const node *n) | 
 | { | 
 |     REQ(n, augassign); | 
 |     n = CHILD(n, 0); | 
 |     switch (STR(n)[0]) { | 
 |         case '+': | 
 |             return Add; | 
 |         case '-': | 
 |             return Sub; | 
 |         case '/': | 
 |             if (STR(n)[1] == '/') | 
 |                 return FloorDiv; | 
 |             else | 
 |                 return Div; | 
 |         case '%': | 
 |             return Mod; | 
 |         case '<': | 
 |             return LShift; | 
 |         case '>': | 
 |             return RShift; | 
 |         case '&': | 
 |             return BitAnd; | 
 |         case '^': | 
 |             return BitXor; | 
 |         case '|': | 
 |             return BitOr; | 
 |         case '*': | 
 |             if (STR(n)[1] == '*') | 
 |                 return Pow; | 
 |             else | 
 |                 return Mult; | 
 |         default: | 
 |             PyErr_Format(PyExc_SystemError, "invalid augassign: %s", STR(n)); | 
 |             return (operator_ty)0; | 
 |     } | 
 | } | 
 |  | 
 | static cmpop_ty | 
 | ast_for_comp_op(struct compiling *c, const node *n) | 
 | { | 
 |     /* comp_op: '<'|'>'|'=='|'>='|'<='|'!='|'in'|'not' 'in'|'is' | 
 |                |'is' 'not' | 
 |     */ | 
 |     REQ(n, comp_op); | 
 |     if (NCH(n) == 1) { | 
 |         n = CHILD(n, 0); | 
 |         switch (TYPE(n)) { | 
 |             case LESS: | 
 |                 return Lt; | 
 |             case GREATER: | 
 |                 return Gt; | 
 |             case EQEQUAL:                       /* == */ | 
 |                 return Eq; | 
 |             case LESSEQUAL: | 
 |                 return LtE; | 
 |             case GREATEREQUAL: | 
 |                 return GtE; | 
 |             case NOTEQUAL: | 
 |                 return NotEq; | 
 |             case NAME: | 
 |                 if (strcmp(STR(n), "in") == 0) | 
 |                     return In; | 
 |                 if (strcmp(STR(n), "is") == 0) | 
 |                     return Is; | 
 |             default: | 
 |                 PyErr_Format(PyExc_SystemError, "invalid comp_op: %s", | 
 |                              STR(n)); | 
 |                 return (cmpop_ty)0; | 
 |         } | 
 |     } | 
 |     else if (NCH(n) == 2) { | 
 |         /* handle "not in" and "is not" */ | 
 |         switch (TYPE(CHILD(n, 0))) { | 
 |             case NAME: | 
 |                 if (strcmp(STR(CHILD(n, 1)), "in") == 0) | 
 |                     return NotIn; | 
 |                 if (strcmp(STR(CHILD(n, 0)), "is") == 0) | 
 |                     return IsNot; | 
 |             default: | 
 |                 PyErr_Format(PyExc_SystemError, "invalid comp_op: %s %s", | 
 |                              STR(CHILD(n, 0)), STR(CHILD(n, 1))); | 
 |                 return (cmpop_ty)0; | 
 |         } | 
 |     } | 
 |     PyErr_Format(PyExc_SystemError, "invalid comp_op: has %d children", | 
 |                  NCH(n)); | 
 |     return (cmpop_ty)0; | 
 | } | 
 |  | 
 | static asdl_seq * | 
 | seq_for_testlist(struct compiling *c, const node *n) | 
 | { | 
 |     /* testlist: test (',' test)* [','] | 
 |        testlist_star_expr: test|star_expr (',' test|star_expr)* [','] | 
 |     */ | 
 |     asdl_seq *seq; | 
 |     expr_ty expression; | 
 |     int i; | 
 |     assert(TYPE(n) == testlist || TYPE(n) == testlist_star_expr || TYPE(n) == testlist_comp); | 
 |  | 
 |     seq = asdl_seq_new((NCH(n) + 1) / 2, c->c_arena); | 
 |     if (!seq) | 
 |         return NULL; | 
 |  | 
 |     for (i = 0; i < NCH(n); i += 2) { | 
 |         const node *ch = CHILD(n, i); | 
 |         assert(TYPE(ch) == test || TYPE(ch) == test_nocond || TYPE(ch) == star_expr); | 
 |  | 
 |         expression = ast_for_expr(c, ch); | 
 |         if (!expression) | 
 |             return NULL; | 
 |  | 
 |         assert(i / 2 < seq->size); | 
 |         asdl_seq_SET(seq, i / 2, expression); | 
 |     } | 
 |     return seq; | 
 | } | 
 |  | 
 | static arg_ty | 
 | compiler_arg(struct compiling *c, const node *n) | 
 | { | 
 |     identifier name; | 
 |     expr_ty annotation = NULL; | 
 |     node *ch; | 
 |  | 
 |     assert(TYPE(n) == tfpdef || TYPE(n) == vfpdef); | 
 |     ch = CHILD(n, 0); | 
 |     name = NEW_IDENTIFIER(ch); | 
 |     if (!name) | 
 |         return NULL; | 
 |     if (forbidden_name(name, ch, 0)) | 
 |         return NULL; | 
 |  | 
 |     if (NCH(n) == 3 && TYPE(CHILD(n, 1)) == COLON) { | 
 |         annotation = ast_for_expr(c, CHILD(n, 2)); | 
 |         if (!annotation) | 
 |             return NULL; | 
 |     } | 
 |  | 
 |     return arg(name, annotation, c->c_arena); | 
 | #if 0 | 
 |     result = Tuple(args, Store, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     if (!set_context(c, result, Store, n)) | 
 |         return NULL; | 
 |     return result; | 
 | #endif | 
 | } | 
 |  | 
 | /* returns -1 if failed to handle keyword only arguments | 
 |    returns new position to keep processing if successful | 
 |                (',' tfpdef ['=' test])* | 
 |                      ^^^ | 
 |    start pointing here | 
 |  */ | 
 | static int | 
 | handle_keywordonly_args(struct compiling *c, const node *n, int start, | 
 |                         asdl_seq *kwonlyargs, asdl_seq *kwdefaults) | 
 | { | 
 |     PyObject *argname; | 
 |     node *ch; | 
 |     expr_ty expression, annotation; | 
 |     arg_ty arg; | 
 |     int i = start; | 
 |     int j = 0; /* index for kwdefaults and kwonlyargs */ | 
 |  | 
 |     if (kwonlyargs == NULL) { | 
 |         ast_error(CHILD(n, start), "named arguments must follow bare *"); | 
 |         return -1; | 
 |     } | 
 |     assert(kwdefaults != NULL); | 
 |     while (i < NCH(n)) { | 
 |         ch = CHILD(n, i); | 
 |         switch (TYPE(ch)) { | 
 |             case vfpdef: | 
 |             case tfpdef: | 
 |                 if (i + 1 < NCH(n) && TYPE(CHILD(n, i + 1)) == EQUAL) { | 
 |                     expression = ast_for_expr(c, CHILD(n, i + 2)); | 
 |                     asdl_seq_SET(kwdefaults, j, expression); | 
 |                     i += 2; /* '=' and test */ | 
 |                 } | 
 |                 else { /* setting NULL if no default value exists */ | 
 |                     asdl_seq_SET(kwdefaults, j, NULL); | 
 |                 } | 
 |                 if (NCH(ch) == 3) { | 
 |                     /* ch is NAME ':' test */ | 
 |                     annotation = ast_for_expr(c, CHILD(ch, 2)); | 
 |                     if (!annotation) { | 
 |                         ast_error(ch, "expected expression"); | 
 |                         goto error; | 
 |                     } | 
 |                 } | 
 |                 else { | 
 |                     annotation = NULL; | 
 |                 } | 
 |                 ch = CHILD(ch, 0); | 
 |                 argname = NEW_IDENTIFIER(ch); | 
 |                 if (!argname) | 
 |                     goto error; | 
 |                 if (forbidden_name(argname, ch, 0)) | 
 |                     goto error; | 
 |                 arg = arg(argname, annotation, c->c_arena); | 
 |                 if (!arg) | 
 |                     goto error; | 
 |                 asdl_seq_SET(kwonlyargs, j++, arg); | 
 |                 i += 2; /* the name and the comma */ | 
 |                 break; | 
 |             case DOUBLESTAR: | 
 |                 return i; | 
 |             default: | 
 |                 ast_error(ch, "unexpected node"); | 
 |                 goto error; | 
 |         } | 
 |     } | 
 |     return i; | 
 |  error: | 
 |     return -1; | 
 | } | 
 |  | 
 | /* Create AST for argument list. */ | 
 |  | 
 | static arguments_ty | 
 | ast_for_arguments(struct compiling *c, const node *n) | 
 | { | 
 |     /* This function handles both typedargslist (function definition) | 
 |        and varargslist (lambda definition). | 
 |  | 
 |        parameters: '(' [typedargslist] ')' | 
 |        typedargslist: ((tfpdef ['=' test] ',')* | 
 |            ('*' [tfpdef] (',' tfpdef ['=' test])* [',' '**' tfpdef] | 
 |            | '**' tfpdef) | 
 |            | tfpdef ['=' test] (',' tfpdef ['=' test])* [',']) | 
 |        tfpdef: NAME [':' test] | 
 |        varargslist: ((vfpdef ['=' test] ',')* | 
 |            ('*' [vfpdef] (',' vfpdef ['=' test])*  [',' '**' vfpdef] | 
 |            | '**' vfpdef) | 
 |            | vfpdef ['=' test] (',' vfpdef ['=' test])* [',']) | 
 |        vfpdef: NAME | 
 |     */ | 
 |     int i, j, k, nposargs = 0, nkwonlyargs = 0; | 
 |     int nposdefaults = 0, found_default = 0; | 
 |     asdl_seq *posargs, *posdefaults, *kwonlyargs, *kwdefaults; | 
 |     identifier vararg = NULL, kwarg = NULL; | 
 |     arg_ty arg; | 
 |     expr_ty varargannotation = NULL, kwargannotation = NULL; | 
 |     node *ch; | 
 |  | 
 |     if (TYPE(n) == parameters) { | 
 |         if (NCH(n) == 2) /* () as argument list */ | 
 |             return arguments(NULL, NULL, NULL, NULL, NULL, NULL, NULL, | 
 |                              NULL, c->c_arena); | 
 |         n = CHILD(n, 1); | 
 |     } | 
 |     assert(TYPE(n) == typedargslist || TYPE(n) == varargslist); | 
 |  | 
 |     /* First count the number of positional args & defaults.  The | 
 |        variable i is the loop index for this for loop and the next. | 
 |        The next loop picks up where the first leaves off. | 
 |     */ | 
 |     for (i = 0; i < NCH(n); i++) { | 
 |         ch = CHILD(n, i); | 
 |         if (TYPE(ch) == STAR) { | 
 |             /* skip star */ | 
 |             i++; | 
 |             if (i < NCH(n) && /* skip argument following star */ | 
 |                 (TYPE(CHILD(n, i)) == tfpdef || | 
 |                  TYPE(CHILD(n, i)) == vfpdef)) { | 
 |                 i++; | 
 |             } | 
 |             break; | 
 |         } | 
 |         if (TYPE(ch) == DOUBLESTAR) break; | 
 |         if (TYPE(ch) == vfpdef || TYPE(ch) == tfpdef) nposargs++; | 
 |         if (TYPE(ch) == EQUAL) nposdefaults++; | 
 |     } | 
 |     /* count the number of keyword only args & | 
 |        defaults for keyword only args */ | 
 |     for ( ; i < NCH(n); ++i) { | 
 |         ch = CHILD(n, i); | 
 |         if (TYPE(ch) == DOUBLESTAR) break; | 
 |         if (TYPE(ch) == tfpdef || TYPE(ch) == vfpdef) nkwonlyargs++; | 
 |     } | 
 |     posargs = (nposargs ? asdl_seq_new(nposargs, c->c_arena) : NULL); | 
 |     if (!posargs && nposargs) | 
 |         goto error; | 
 |     kwonlyargs = (nkwonlyargs ? | 
 |                    asdl_seq_new(nkwonlyargs, c->c_arena) : NULL); | 
 |     if (!kwonlyargs && nkwonlyargs) | 
 |         goto error; | 
 |     posdefaults = (nposdefaults ? | 
 |                     asdl_seq_new(nposdefaults, c->c_arena) : NULL); | 
 |     if (!posdefaults && nposdefaults) | 
 |         goto error; | 
 |     /* The length of kwonlyargs and kwdefaults are same | 
 |        since we set NULL as default for keyword only argument w/o default | 
 |        - we have sequence data structure, but no dictionary */ | 
 |     kwdefaults = (nkwonlyargs ? | 
 |                    asdl_seq_new(nkwonlyargs, c->c_arena) : NULL); | 
 |     if (!kwdefaults && nkwonlyargs) | 
 |         goto error; | 
 |  | 
 |     if (nposargs + nkwonlyargs > 255) { | 
 |         ast_error(n, "more than 255 arguments"); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     /* tfpdef: NAME [':' test] | 
 |        vfpdef: NAME | 
 |     */ | 
 |     i = 0; | 
 |     j = 0;  /* index for defaults */ | 
 |     k = 0;  /* index for args */ | 
 |     while (i < NCH(n)) { | 
 |         ch = CHILD(n, i); | 
 |         switch (TYPE(ch)) { | 
 |             case tfpdef: | 
 |             case vfpdef: | 
 |                 /* XXX Need to worry about checking if TYPE(CHILD(n, i+1)) is | 
 |                    anything other than EQUAL or a comma? */ | 
 |                 /* XXX Should NCH(n) check be made a separate check? */ | 
 |                 if (i + 1 < NCH(n) && TYPE(CHILD(n, i + 1)) == EQUAL) { | 
 |                     expr_ty expression = ast_for_expr(c, CHILD(n, i + 2)); | 
 |                     if (!expression) | 
 |                         goto error; | 
 |                     assert(posdefaults != NULL); | 
 |                     asdl_seq_SET(posdefaults, j++, expression); | 
 |                     i += 2; | 
 |                     found_default = 1; | 
 |                 } | 
 |                 else if (found_default) { | 
 |                     ast_error(n, | 
 |                              "non-default argument follows default argument"); | 
 |                     goto error; | 
 |                 } | 
 |                 arg = compiler_arg(c, ch); | 
 |                 if (!arg) | 
 |                     goto error; | 
 |                 asdl_seq_SET(posargs, k++, arg); | 
 |                 i += 2; /* the name and the comma */ | 
 |                 break; | 
 |             case STAR: | 
 |                 if (i+1 >= NCH(n)) { | 
 |                     ast_error(CHILD(n, i), | 
 |                         "named arguments must follow bare *"); | 
 |                     goto error; | 
 |                 } | 
 |                 ch = CHILD(n, i+1);  /* tfpdef or COMMA */ | 
 |                 if (TYPE(ch) == COMMA) { | 
 |                     int res = 0; | 
 |                     i += 2; /* now follows keyword only arguments */ | 
 |                     res = handle_keywordonly_args(c, n, i, | 
 |                                                   kwonlyargs, kwdefaults); | 
 |                     if (res == -1) goto error; | 
 |                     i = res; /* res has new position to process */ | 
 |                 } | 
 |                 else { | 
 |                     vararg = NEW_IDENTIFIER(CHILD(ch, 0)); | 
 |                     if (!vararg) | 
 |                         return NULL; | 
 |                     if (forbidden_name(vararg, CHILD(ch, 0), 0)) | 
 |                         return NULL; | 
 |                     if (NCH(ch) > 1) { | 
 |                         /* there is an annotation on the vararg */ | 
 |                         varargannotation = ast_for_expr(c, CHILD(ch, 2)); | 
 |                     } | 
 |                     i += 3; | 
 |                     if (i < NCH(n) && (TYPE(CHILD(n, i)) == tfpdef | 
 |                                     || TYPE(CHILD(n, i)) == vfpdef)) { | 
 |                         int res = 0; | 
 |                         res = handle_keywordonly_args(c, n, i, | 
 |                                                       kwonlyargs, kwdefaults); | 
 |                         if (res == -1) goto error; | 
 |                         i = res; /* res has new position to process */ | 
 |                     } | 
 |                 } | 
 |                 break; | 
 |             case DOUBLESTAR: | 
 |                 ch = CHILD(n, i+1);  /* tfpdef */ | 
 |                 assert(TYPE(ch) == tfpdef || TYPE(ch) == vfpdef); | 
 |                 kwarg = NEW_IDENTIFIER(CHILD(ch, 0)); | 
 |                 if (NCH(ch) > 1) { | 
 |                     /* there is an annotation on the kwarg */ | 
 |                     kwargannotation = ast_for_expr(c, CHILD(ch, 2)); | 
 |                 } | 
 |                 if (!kwarg) | 
 |                     goto error; | 
 |                 if (forbidden_name(kwarg, CHILD(ch, 0), 0)) | 
 |                     goto error; | 
 |                 i += 3; | 
 |                 break; | 
 |             default: | 
 |                 PyErr_Format(PyExc_SystemError, | 
 |                              "unexpected node in varargslist: %d @ %d", | 
 |                              TYPE(ch), i); | 
 |                 goto error; | 
 |         } | 
 |     } | 
 |     return arguments(posargs, vararg, varargannotation, kwonlyargs, kwarg, | 
 |                     kwargannotation, posdefaults, kwdefaults, c->c_arena); | 
 |  error: | 
 |     Py_XDECREF(vararg); | 
 |     Py_XDECREF(kwarg); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_dotted_name(struct compiling *c, const node *n) | 
 | { | 
 |     expr_ty e; | 
 |     identifier id; | 
 |     int lineno, col_offset; | 
 |     int i; | 
 |  | 
 |     REQ(n, dotted_name); | 
 |  | 
 |     lineno = LINENO(n); | 
 |     col_offset = n->n_col_offset; | 
 |  | 
 |     id = NEW_IDENTIFIER(CHILD(n, 0)); | 
 |     if (!id) | 
 |         return NULL; | 
 |     e = Name(id, Load, lineno, col_offset, c->c_arena); | 
 |     if (!e) | 
 |         return NULL; | 
 |  | 
 |     for (i = 2; i < NCH(n); i+=2) { | 
 |         id = NEW_IDENTIFIER(CHILD(n, i)); | 
 |         if (!id) | 
 |             return NULL; | 
 |         e = Attribute(e, id, Load, lineno, col_offset, c->c_arena); | 
 |         if (!e) | 
 |             return NULL; | 
 |     } | 
 |  | 
 |     return e; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_decorator(struct compiling *c, const node *n) | 
 | { | 
 |     /* decorator: '@' dotted_name [ '(' [arglist] ')' ] NEWLINE */ | 
 |     expr_ty d = NULL; | 
 |     expr_ty name_expr; | 
 |  | 
 |     REQ(n, decorator); | 
 |     REQ(CHILD(n, 0), AT); | 
 |     REQ(RCHILD(n, -1), NEWLINE); | 
 |  | 
 |     name_expr = ast_for_dotted_name(c, CHILD(n, 1)); | 
 |     if (!name_expr) | 
 |         return NULL; | 
 |  | 
 |     if (NCH(n) == 3) { /* No arguments */ | 
 |         d = name_expr; | 
 |         name_expr = NULL; | 
 |     } | 
 |     else if (NCH(n) == 5) { /* Call with no arguments */ | 
 |         d = Call(name_expr, NULL, NULL, NULL, NULL, LINENO(n), | 
 |                  n->n_col_offset, c->c_arena); | 
 |         if (!d) | 
 |             return NULL; | 
 |         name_expr = NULL; | 
 |     } | 
 |     else { | 
 |         d = ast_for_call(c, CHILD(n, 3), name_expr); | 
 |         if (!d) | 
 |             return NULL; | 
 |         name_expr = NULL; | 
 |     } | 
 |  | 
 |     return d; | 
 | } | 
 |  | 
 | static asdl_seq* | 
 | ast_for_decorators(struct compiling *c, const node *n) | 
 | { | 
 |     asdl_seq* decorator_seq; | 
 |     expr_ty d; | 
 |     int i; | 
 |  | 
 |     REQ(n, decorators); | 
 |     decorator_seq = asdl_seq_new(NCH(n), c->c_arena); | 
 |     if (!decorator_seq) | 
 |         return NULL; | 
 |  | 
 |     for (i = 0; i < NCH(n); i++) { | 
 |         d = ast_for_decorator(c, CHILD(n, i)); | 
 |             if (!d) | 
 |                 return NULL; | 
 |             asdl_seq_SET(decorator_seq, i, d); | 
 |     } | 
 |     return decorator_seq; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_funcdef(struct compiling *c, const node *n, asdl_seq *decorator_seq) | 
 | { | 
 |     /* funcdef: 'def' NAME parameters ['->' test] ':' suite */ | 
 |     identifier name; | 
 |     arguments_ty args; | 
 |     asdl_seq *body; | 
 |     expr_ty returns = NULL; | 
 |     int name_i = 1; | 
 |  | 
 |     REQ(n, funcdef); | 
 |  | 
 |     name = NEW_IDENTIFIER(CHILD(n, name_i)); | 
 |     if (!name) | 
 |         return NULL; | 
 |     if (forbidden_name(name, CHILD(n, name_i), 0)) | 
 |         return NULL; | 
 |     args = ast_for_arguments(c, CHILD(n, name_i + 1)); | 
 |     if (!args) | 
 |         return NULL; | 
 |     if (TYPE(CHILD(n, name_i+2)) == RARROW) { | 
 |         returns = ast_for_expr(c, CHILD(n, name_i + 3)); | 
 |         if (!returns) | 
 |                 return NULL; | 
 |         name_i += 2; | 
 |     } | 
 |     body = ast_for_suite(c, CHILD(n, name_i + 3)); | 
 |     if (!body) | 
 |         return NULL; | 
 |  | 
 |     return FunctionDef(name, args, body, decorator_seq, returns, LINENO(n), | 
 |                        n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_decorated(struct compiling *c, const node *n) | 
 | { | 
 |     /* decorated: decorators (classdef | funcdef) */ | 
 |     stmt_ty thing = NULL; | 
 |     asdl_seq *decorator_seq = NULL; | 
 |  | 
 |     REQ(n, decorated); | 
 |  | 
 |     decorator_seq = ast_for_decorators(c, CHILD(n, 0)); | 
 |     if (!decorator_seq) | 
 |       return NULL; | 
 |  | 
 |     assert(TYPE(CHILD(n, 1)) == funcdef || | 
 |            TYPE(CHILD(n, 1)) == classdef); | 
 |  | 
 |     if (TYPE(CHILD(n, 1)) == funcdef) { | 
 |       thing = ast_for_funcdef(c, CHILD(n, 1), decorator_seq); | 
 |     } else if (TYPE(CHILD(n, 1)) == classdef) { | 
 |       thing = ast_for_classdef(c, CHILD(n, 1), decorator_seq); | 
 |     } | 
 |     /* we count the decorators in when talking about the class' or | 
 |      * function's line number */ | 
 |     if (thing) { | 
 |         thing->lineno = LINENO(n); | 
 |         thing->col_offset = n->n_col_offset; | 
 |     } | 
 |     return thing; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_lambdef(struct compiling *c, const node *n) | 
 | { | 
 |     /* lambdef: 'lambda' [varargslist] ':' test | 
 |        lambdef_nocond: 'lambda' [varargslist] ':' test_nocond */ | 
 |     arguments_ty args; | 
 |     expr_ty expression; | 
 |  | 
 |     if (NCH(n) == 3) { | 
 |         args = arguments(NULL, NULL, NULL, NULL, NULL, NULL, NULL, | 
 |                          NULL, c->c_arena); | 
 |         if (!args) | 
 |             return NULL; | 
 |         expression = ast_for_expr(c, CHILD(n, 2)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |     } | 
 |     else { | 
 |         args = ast_for_arguments(c, CHILD(n, 1)); | 
 |         if (!args) | 
 |             return NULL; | 
 |         expression = ast_for_expr(c, CHILD(n, 3)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |     } | 
 |  | 
 |     return Lambda(args, expression, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_ifexpr(struct compiling *c, const node *n) | 
 | { | 
 |     /* test: or_test 'if' or_test 'else' test */ | 
 |     expr_ty expression, body, orelse; | 
 |  | 
 |     assert(NCH(n) == 5); | 
 |     body = ast_for_expr(c, CHILD(n, 0)); | 
 |     if (!body) | 
 |         return NULL; | 
 |     expression = ast_for_expr(c, CHILD(n, 2)); | 
 |     if (!expression) | 
 |         return NULL; | 
 |     orelse = ast_for_expr(c, CHILD(n, 4)); | 
 |     if (!orelse) | 
 |         return NULL; | 
 |     return IfExp(expression, body, orelse, LINENO(n), n->n_col_offset, | 
 |                  c->c_arena); | 
 | } | 
 |  | 
 | /* | 
 |    Count the number of 'for' loops in a comprehension. | 
 |  | 
 |    Helper for ast_for_comprehension(). | 
 | */ | 
 |  | 
 | static int | 
 | count_comp_fors(struct compiling *c, const node *n) | 
 | { | 
 |     int n_fors = 0; | 
 |  | 
 |   count_comp_for: | 
 |     n_fors++; | 
 |     REQ(n, comp_for); | 
 |     if (NCH(n) == 5) | 
 |         n = CHILD(n, 4); | 
 |     else | 
 |         return n_fors; | 
 |   count_comp_iter: | 
 |     REQ(n, comp_iter); | 
 |     n = CHILD(n, 0); | 
 |     if (TYPE(n) == comp_for) | 
 |         goto count_comp_for; | 
 |     else if (TYPE(n) == comp_if) { | 
 |         if (NCH(n) == 3) { | 
 |             n = CHILD(n, 2); | 
 |             goto count_comp_iter; | 
 |         } | 
 |         else | 
 |             return n_fors; | 
 |     } | 
 |  | 
 |     /* Should never be reached */ | 
 |     PyErr_SetString(PyExc_SystemError, | 
 |                     "logic error in count_comp_fors"); | 
 |     return -1; | 
 | } | 
 |  | 
 | /* Count the number of 'if' statements in a comprehension. | 
 |  | 
 |    Helper for ast_for_comprehension(). | 
 | */ | 
 |  | 
 | static int | 
 | count_comp_ifs(struct compiling *c, const node *n) | 
 | { | 
 |     int n_ifs = 0; | 
 |  | 
 |     while (1) { | 
 |         REQ(n, comp_iter); | 
 |         if (TYPE(CHILD(n, 0)) == comp_for) | 
 |             return n_ifs; | 
 |         n = CHILD(n, 0); | 
 |         REQ(n, comp_if); | 
 |         n_ifs++; | 
 |         if (NCH(n) == 2) | 
 |             return n_ifs; | 
 |         n = CHILD(n, 2); | 
 |     } | 
 | } | 
 |  | 
 | static asdl_seq * | 
 | ast_for_comprehension(struct compiling *c, const node *n) | 
 | { | 
 |     int i, n_fors; | 
 |     asdl_seq *comps; | 
 |  | 
 |     n_fors = count_comp_fors(c, n); | 
 |     if (n_fors == -1) | 
 |         return NULL; | 
 |  | 
 |     comps = asdl_seq_new(n_fors, c->c_arena); | 
 |     if (!comps) | 
 |         return NULL; | 
 |  | 
 |     for (i = 0; i < n_fors; i++) { | 
 |         comprehension_ty comp; | 
 |         asdl_seq *t; | 
 |         expr_ty expression, first; | 
 |         node *for_ch; | 
 |  | 
 |         REQ(n, comp_for); | 
 |  | 
 |         for_ch = CHILD(n, 1); | 
 |         t = ast_for_exprlist(c, for_ch, Store); | 
 |         if (!t) | 
 |             return NULL; | 
 |         expression = ast_for_expr(c, CHILD(n, 3)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |  | 
 |         /* Check the # of children rather than the length of t, since | 
 |            (x for x, in ...) has 1 element in t, but still requires a Tuple. */ | 
 |         first = (expr_ty)asdl_seq_GET(t, 0); | 
 |         if (NCH(for_ch) == 1) | 
 |             comp = comprehension(first, expression, NULL, c->c_arena); | 
 |         else | 
 |             comp = comprehension(Tuple(t, Store, first->lineno, first->col_offset, | 
 |                                      c->c_arena), | 
 |                                expression, NULL, c->c_arena); | 
 |         if (!comp) | 
 |             return NULL; | 
 |  | 
 |         if (NCH(n) == 5) { | 
 |             int j, n_ifs; | 
 |             asdl_seq *ifs; | 
 |  | 
 |             n = CHILD(n, 4); | 
 |             n_ifs = count_comp_ifs(c, n); | 
 |             if (n_ifs == -1) | 
 |                 return NULL; | 
 |  | 
 |             ifs = asdl_seq_new(n_ifs, c->c_arena); | 
 |             if (!ifs) | 
 |                 return NULL; | 
 |  | 
 |             for (j = 0; j < n_ifs; j++) { | 
 |                 REQ(n, comp_iter); | 
 |                 n = CHILD(n, 0); | 
 |                 REQ(n, comp_if); | 
 |  | 
 |                 expression = ast_for_expr(c, CHILD(n, 1)); | 
 |                 if (!expression) | 
 |                     return NULL; | 
 |                 asdl_seq_SET(ifs, j, expression); | 
 |                 if (NCH(n) == 3) | 
 |                     n = CHILD(n, 2); | 
 |             } | 
 |             /* on exit, must guarantee that n is a comp_for */ | 
 |             if (TYPE(n) == comp_iter) | 
 |                 n = CHILD(n, 0); | 
 |             comp->ifs = ifs; | 
 |         } | 
 |         asdl_seq_SET(comps, i, comp); | 
 |     } | 
 |     return comps; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_itercomp(struct compiling *c, const node *n, int type) | 
 | { | 
 |     /* testlist_comp: test ( comp_for | (',' test)* [','] ) | 
 |        argument: [test '='] test [comp_for]       # Really [keyword '='] test */ | 
 |     expr_ty elt; | 
 |     asdl_seq *comps; | 
 |  | 
 |     assert(NCH(n) > 1); | 
 |  | 
 |     elt = ast_for_expr(c, CHILD(n, 0)); | 
 |     if (!elt) | 
 |         return NULL; | 
 |  | 
 |     comps = ast_for_comprehension(c, CHILD(n, 1)); | 
 |     if (!comps) | 
 |         return NULL; | 
 |  | 
 |     if (type == COMP_GENEXP) | 
 |         return GeneratorExp(elt, comps, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     else if (type == COMP_LISTCOMP) | 
 |         return ListComp(elt, comps, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     else if (type == COMP_SETCOMP) | 
 |         return SetComp(elt, comps, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     else | 
 |         /* Should never happen */ | 
 |         return NULL; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_dictcomp(struct compiling *c, const node *n) | 
 | { | 
 |     expr_ty key, value; | 
 |     asdl_seq *comps; | 
 |  | 
 |     assert(NCH(n) > 3); | 
 |     REQ(CHILD(n, 1), COLON); | 
 |  | 
 |     key = ast_for_expr(c, CHILD(n, 0)); | 
 |     if (!key) | 
 |         return NULL; | 
 |     value = ast_for_expr(c, CHILD(n, 2)); | 
 |     if (!value) | 
 |         return NULL; | 
 |  | 
 |     comps = ast_for_comprehension(c, CHILD(n, 3)); | 
 |     if (!comps) | 
 |         return NULL; | 
 |  | 
 |     return DictComp(key, value, comps, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_genexp(struct compiling *c, const node *n) | 
 | { | 
 |     assert(TYPE(n) == (testlist_comp) || TYPE(n) == (argument)); | 
 |     return ast_for_itercomp(c, n, COMP_GENEXP); | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_listcomp(struct compiling *c, const node *n) | 
 | { | 
 |     assert(TYPE(n) == (testlist_comp)); | 
 |     return ast_for_itercomp(c, n, COMP_LISTCOMP); | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_setcomp(struct compiling *c, const node *n) | 
 | { | 
 |     assert(TYPE(n) == (dictorsetmaker)); | 
 |     return ast_for_itercomp(c, n, COMP_SETCOMP); | 
 | } | 
 |  | 
 |  | 
 | static expr_ty | 
 | ast_for_atom(struct compiling *c, const node *n) | 
 | { | 
 |     /* atom: '(' [yield_expr|testlist_comp] ')' | '[' [testlist_comp] ']' | 
 |        | '{' [dictmaker|testlist_comp] '}' | NAME | NUMBER | STRING+ | 
 |        | '...' | 'None' | 'True' | 'False' | 
 |     */ | 
 |     node *ch = CHILD(n, 0); | 
 |     int bytesmode = 0; | 
 |  | 
 |     switch (TYPE(ch)) { | 
 |     case NAME: { | 
 |         /* All names start in Load context, but may later be | 
 |            changed. */ | 
 |         PyObject *name = NEW_IDENTIFIER(ch); | 
 |         if (!name) | 
 |             return NULL; | 
 |         return Name(name, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     case STRING: { | 
 |         PyObject *str = parsestrplus(c, n, &bytesmode); | 
 |         if (!str) { | 
 |             if (PyErr_ExceptionMatches(PyExc_UnicodeError)) { | 
 |                 PyObject *type, *value, *tback, *errstr; | 
 |                 PyErr_Fetch(&type, &value, &tback); | 
 |                 errstr = PyObject_Str(value); | 
 |                 if (errstr) { | 
 |                     char *s = ""; | 
 |                     char buf[128]; | 
 |                     s = _PyUnicode_AsString(errstr); | 
 |                     PyOS_snprintf(buf, sizeof(buf), "(unicode error) %s", s); | 
 |                     ast_error(n, buf); | 
 |                     Py_DECREF(errstr); | 
 |                 } else { | 
 |                     ast_error(n, "(unicode error) unknown error"); | 
 |                 } | 
 |                 Py_DECREF(type); | 
 |                 Py_DECREF(value); | 
 |                 Py_XDECREF(tback); | 
 |             } | 
 |             return NULL; | 
 |         } | 
 |         PyArena_AddPyObject(c->c_arena, str); | 
 |         if (bytesmode) | 
 |             return Bytes(str, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         else | 
 |             return Str(str, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     case NUMBER: { | 
 |         PyObject *pynum = parsenumber(c, STR(ch)); | 
 |         if (!pynum) | 
 |             return NULL; | 
 |  | 
 |         PyArena_AddPyObject(c->c_arena, pynum); | 
 |         return Num(pynum, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     case ELLIPSIS: /* Ellipsis */ | 
 |         return Ellipsis(LINENO(n), n->n_col_offset, c->c_arena); | 
 |     case LPAR: /* some parenthesized expressions */ | 
 |         ch = CHILD(n, 1); | 
 |  | 
 |         if (TYPE(ch) == RPAR) | 
 |             return Tuple(NULL, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |  | 
 |         if (TYPE(ch) == yield_expr) | 
 |             return ast_for_expr(c, ch); | 
 |  | 
 |         /* testlist_comp: test ( comp_for | (',' test)* [','] ) */ | 
 |         if ((NCH(ch) > 1) && (TYPE(CHILD(ch, 1)) == comp_for)) | 
 |             return ast_for_genexp(c, ch); | 
 |  | 
 |         return ast_for_testlist(c, ch); | 
 |     case LSQB: /* list (or list comprehension) */ | 
 |         ch = CHILD(n, 1); | 
 |  | 
 |         if (TYPE(ch) == RSQB) | 
 |             return List(NULL, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |  | 
 |         REQ(ch, testlist_comp); | 
 |         if (NCH(ch) == 1 || TYPE(CHILD(ch, 1)) == COMMA) { | 
 |             asdl_seq *elts = seq_for_testlist(c, ch); | 
 |             if (!elts) | 
 |                 return NULL; | 
 |  | 
 |             return List(elts, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         } | 
 |         else | 
 |             return ast_for_listcomp(c, ch); | 
 |     case LBRACE: { | 
 |         /* dictorsetmaker: test ':' test (',' test ':' test)* [','] | | 
 |          *                 test (gen_for | (',' test)* [','])  */ | 
 |         int i, size; | 
 |         asdl_seq *keys, *values; | 
 |  | 
 |         ch = CHILD(n, 1); | 
 |         if (TYPE(ch) == RBRACE) { | 
 |             /* it's an empty dict */ | 
 |             return Dict(NULL, NULL, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         } else if (NCH(ch) == 1 || TYPE(CHILD(ch, 1)) == COMMA) { | 
 |             /* it's a simple set */ | 
 |             asdl_seq *elts; | 
 |             size = (NCH(ch) + 1) / 2; /* +1 in case no trailing comma */ | 
 |             elts = asdl_seq_new(size, c->c_arena); | 
 |             if (!elts) | 
 |                 return NULL; | 
 |             for (i = 0; i < NCH(ch); i += 2) { | 
 |                 expr_ty expression; | 
 |                 expression = ast_for_expr(c, CHILD(ch, i)); | 
 |                 if (!expression) | 
 |                     return NULL; | 
 |                 asdl_seq_SET(elts, i / 2, expression); | 
 |             } | 
 |             return Set(elts, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         } else if (TYPE(CHILD(ch, 1)) == comp_for) { | 
 |             /* it's a set comprehension */ | 
 |             return ast_for_setcomp(c, ch); | 
 |         } else if (NCH(ch) > 3 && TYPE(CHILD(ch, 3)) == comp_for) { | 
 |             return ast_for_dictcomp(c, ch); | 
 |         } else { | 
 |             /* it's a dict */ | 
 |             size = (NCH(ch) + 1) / 4; /* +1 in case no trailing comma */ | 
 |             keys = asdl_seq_new(size, c->c_arena); | 
 |             if (!keys) | 
 |                 return NULL; | 
 |  | 
 |             values = asdl_seq_new(size, c->c_arena); | 
 |             if (!values) | 
 |                 return NULL; | 
 |  | 
 |             for (i = 0; i < NCH(ch); i += 4) { | 
 |                 expr_ty expression; | 
 |  | 
 |                 expression = ast_for_expr(c, CHILD(ch, i)); | 
 |                 if (!expression) | 
 |                     return NULL; | 
 |  | 
 |                 asdl_seq_SET(keys, i / 4, expression); | 
 |  | 
 |                 expression = ast_for_expr(c, CHILD(ch, i + 2)); | 
 |                 if (!expression) | 
 |                     return NULL; | 
 |  | 
 |                 asdl_seq_SET(values, i / 4, expression); | 
 |             } | 
 |             return Dict(keys, values, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         } | 
 |     } | 
 |     default: | 
 |         PyErr_Format(PyExc_SystemError, "unhandled atom %d", TYPE(ch)); | 
 |         return NULL; | 
 |     } | 
 | } | 
 |  | 
 | static slice_ty | 
 | ast_for_slice(struct compiling *c, const node *n) | 
 | { | 
 |     node *ch; | 
 |     expr_ty lower = NULL, upper = NULL, step = NULL; | 
 |  | 
 |     REQ(n, subscript); | 
 |  | 
 |     /* | 
 |        subscript: test | [test] ':' [test] [sliceop] | 
 |        sliceop: ':' [test] | 
 |     */ | 
 |     ch = CHILD(n, 0); | 
 |     if (NCH(n) == 1 && TYPE(ch) == test) { | 
 |         /* 'step' variable hold no significance in terms of being used over | 
 |            other vars */ | 
 |         step = ast_for_expr(c, ch); | 
 |         if (!step) | 
 |             return NULL; | 
 |  | 
 |         return Index(step, c->c_arena); | 
 |     } | 
 |  | 
 |     if (TYPE(ch) == test) { | 
 |         lower = ast_for_expr(c, ch); | 
 |         if (!lower) | 
 |             return NULL; | 
 |     } | 
 |  | 
 |     /* If there's an upper bound it's in the second or third position. */ | 
 |     if (TYPE(ch) == COLON) { | 
 |         if (NCH(n) > 1) { | 
 |             node *n2 = CHILD(n, 1); | 
 |  | 
 |             if (TYPE(n2) == test) { | 
 |                 upper = ast_for_expr(c, n2); | 
 |                 if (!upper) | 
 |                     return NULL; | 
 |             } | 
 |         } | 
 |     } else if (NCH(n) > 2) { | 
 |         node *n2 = CHILD(n, 2); | 
 |  | 
 |         if (TYPE(n2) == test) { | 
 |             upper = ast_for_expr(c, n2); | 
 |             if (!upper) | 
 |                 return NULL; | 
 |         } | 
 |     } | 
 |  | 
 |     ch = CHILD(n, NCH(n) - 1); | 
 |     if (TYPE(ch) == sliceop) { | 
 |         if (NCH(ch) != 1) { | 
 |             ch = CHILD(ch, 1); | 
 |             if (TYPE(ch) == test) { | 
 |                 step = ast_for_expr(c, ch); | 
 |                 if (!step) | 
 |                     return NULL; | 
 |             } | 
 |         } | 
 |     } | 
 |  | 
 |     return Slice(lower, upper, step, c->c_arena); | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_binop(struct compiling *c, const node *n) | 
 | { | 
 |     /* Must account for a sequence of expressions. | 
 |        How should A op B op C by represented? | 
 |        BinOp(BinOp(A, op, B), op, C). | 
 |     */ | 
 |  | 
 |     int i, nops; | 
 |     expr_ty expr1, expr2, result; | 
 |     operator_ty newoperator; | 
 |  | 
 |     expr1 = ast_for_expr(c, CHILD(n, 0)); | 
 |     if (!expr1) | 
 |         return NULL; | 
 |  | 
 |     expr2 = ast_for_expr(c, CHILD(n, 2)); | 
 |     if (!expr2) | 
 |         return NULL; | 
 |  | 
 |     newoperator = get_operator(CHILD(n, 1)); | 
 |     if (!newoperator) | 
 |         return NULL; | 
 |  | 
 |     result = BinOp(expr1, newoperator, expr2, LINENO(n), n->n_col_offset, | 
 |                    c->c_arena); | 
 |     if (!result) | 
 |         return NULL; | 
 |  | 
 |     nops = (NCH(n) - 1) / 2; | 
 |     for (i = 1; i < nops; i++) { | 
 |         expr_ty tmp_result, tmp; | 
 |         const node* next_oper = CHILD(n, i * 2 + 1); | 
 |  | 
 |         newoperator = get_operator(next_oper); | 
 |         if (!newoperator) | 
 |             return NULL; | 
 |  | 
 |         tmp = ast_for_expr(c, CHILD(n, i * 2 + 2)); | 
 |         if (!tmp) | 
 |             return NULL; | 
 |  | 
 |         tmp_result = BinOp(result, newoperator, tmp, | 
 |                            LINENO(next_oper), next_oper->n_col_offset, | 
 |                            c->c_arena); | 
 |         if (!tmp_result) | 
 |             return NULL; | 
 |         result = tmp_result; | 
 |     } | 
 |     return result; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_trailer(struct compiling *c, const node *n, expr_ty left_expr) | 
 | { | 
 |     /* trailer: '(' [arglist] ')' | '[' subscriptlist ']' | '.' NAME | 
 |        subscriptlist: subscript (',' subscript)* [','] | 
 |        subscript: '.' '.' '.' | test | [test] ':' [test] [sliceop] | 
 |      */ | 
 |     REQ(n, trailer); | 
 |     if (TYPE(CHILD(n, 0)) == LPAR) { | 
 |         if (NCH(n) == 2) | 
 |             return Call(left_expr, NULL, NULL, NULL, NULL, LINENO(n), | 
 |                         n->n_col_offset, c->c_arena); | 
 |         else | 
 |             return ast_for_call(c, CHILD(n, 1), left_expr); | 
 |     } | 
 |     else if (TYPE(CHILD(n, 0)) == DOT ) { | 
 |         PyObject *attr_id = NEW_IDENTIFIER(CHILD(n, 1)); | 
 |         if (!attr_id) | 
 |             return NULL; | 
 |         return Attribute(left_expr, attr_id, Load, | 
 |                          LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     else { | 
 |         REQ(CHILD(n, 0), LSQB); | 
 |         REQ(CHILD(n, 2), RSQB); | 
 |         n = CHILD(n, 1); | 
 |         if (NCH(n) == 1) { | 
 |             slice_ty slc = ast_for_slice(c, CHILD(n, 0)); | 
 |             if (!slc) | 
 |                 return NULL; | 
 |             return Subscript(left_expr, slc, Load, LINENO(n), n->n_col_offset, | 
 |                              c->c_arena); | 
 |         } | 
 |         else { | 
 |             /* The grammar is ambiguous here. The ambiguity is resolved | 
 |                by treating the sequence as a tuple literal if there are | 
 |                no slice features. | 
 |             */ | 
 |             int j; | 
 |             slice_ty slc; | 
 |             expr_ty e; | 
 |             int simple = 1; | 
 |             asdl_seq *slices, *elts; | 
 |             slices = asdl_seq_new((NCH(n) + 1) / 2, c->c_arena); | 
 |             if (!slices) | 
 |                 return NULL; | 
 |             for (j = 0; j < NCH(n); j += 2) { | 
 |                 slc = ast_for_slice(c, CHILD(n, j)); | 
 |                 if (!slc) | 
 |                     return NULL; | 
 |                 if (slc->kind != Index_kind) | 
 |                     simple = 0; | 
 |                 asdl_seq_SET(slices, j / 2, slc); | 
 |             } | 
 |             if (!simple) { | 
 |                 return Subscript(left_expr, ExtSlice(slices, c->c_arena), | 
 |                                  Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |             } | 
 |             /* extract Index values and put them in a Tuple */ | 
 |             elts = asdl_seq_new(asdl_seq_LEN(slices), c->c_arena); | 
 |             if (!elts) | 
 |                 return NULL; | 
 |             for (j = 0; j < asdl_seq_LEN(slices); ++j) { | 
 |                 slc = (slice_ty)asdl_seq_GET(slices, j); | 
 |                 assert(slc->kind == Index_kind  && slc->v.Index.value); | 
 |                 asdl_seq_SET(elts, j, slc->v.Index.value); | 
 |             } | 
 |             e = Tuple(elts, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |             if (!e) | 
 |                 return NULL; | 
 |             return Subscript(left_expr, Index(e, c->c_arena), | 
 |                              Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         } | 
 |     } | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_factor(struct compiling *c, const node *n) | 
 | { | 
 |     node *pfactor, *ppower, *patom, *pnum; | 
 |     expr_ty expression; | 
 |  | 
 |     /* If the unary - operator is applied to a constant, don't generate | 
 |        a UNARY_NEGATIVE opcode.  Just store the approriate value as a | 
 |        constant.  The peephole optimizer already does something like | 
 |        this but it doesn't handle the case where the constant is | 
 |        (sys.maxint - 1).  In that case, we want a PyIntObject, not a | 
 |        PyLongObject. | 
 |     */ | 
 |     if (TYPE(CHILD(n, 0)) == MINUS | 
 |         && NCH(n) == 2 | 
 |         && TYPE((pfactor = CHILD(n, 1))) == factor | 
 |         && NCH(pfactor) == 1 | 
 |         && TYPE((ppower = CHILD(pfactor, 0))) == power | 
 |         && NCH(ppower) == 1 | 
 |         && TYPE((patom = CHILD(ppower, 0))) == atom | 
 |         && TYPE((pnum = CHILD(patom, 0))) == NUMBER) { | 
 |         char *s = PyObject_MALLOC(strlen(STR(pnum)) + 2); | 
 |         if (s == NULL) | 
 |             return NULL; | 
 |         s[0] = '-'; | 
 |         strcpy(s + 1, STR(pnum)); | 
 |         PyObject_FREE(STR(pnum)); | 
 |         STR(pnum) = s; | 
 |         return ast_for_atom(c, patom); | 
 |     } | 
 |  | 
 |     expression = ast_for_expr(c, CHILD(n, 1)); | 
 |     if (!expression) | 
 |         return NULL; | 
 |  | 
 |     switch (TYPE(CHILD(n, 0))) { | 
 |         case PLUS: | 
 |             return UnaryOp(UAdd, expression, LINENO(n), n->n_col_offset, | 
 |                            c->c_arena); | 
 |         case MINUS: | 
 |             return UnaryOp(USub, expression, LINENO(n), n->n_col_offset, | 
 |                            c->c_arena); | 
 |         case TILDE: | 
 |             return UnaryOp(Invert, expression, LINENO(n), | 
 |                            n->n_col_offset, c->c_arena); | 
 |     } | 
 |     PyErr_Format(PyExc_SystemError, "unhandled factor: %d", | 
 |                  TYPE(CHILD(n, 0))); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_power(struct compiling *c, const node *n) | 
 | { | 
 |     /* power: atom trailer* ('**' factor)* | 
 |      */ | 
 |     int i; | 
 |     expr_ty e, tmp; | 
 |     REQ(n, power); | 
 |     e = ast_for_atom(c, CHILD(n, 0)); | 
 |     if (!e) | 
 |         return NULL; | 
 |     if (NCH(n) == 1) | 
 |         return e; | 
 |     for (i = 1; i < NCH(n); i++) { | 
 |         node *ch = CHILD(n, i); | 
 |         if (TYPE(ch) != trailer) | 
 |             break; | 
 |         tmp = ast_for_trailer(c, ch, e); | 
 |         if (!tmp) | 
 |             return NULL; | 
 |         tmp->lineno = e->lineno; | 
 |         tmp->col_offset = e->col_offset; | 
 |         e = tmp; | 
 |     } | 
 |     if (TYPE(CHILD(n, NCH(n) - 1)) == factor) { | 
 |         expr_ty f = ast_for_expr(c, CHILD(n, NCH(n) - 1)); | 
 |         if (!f) | 
 |             return NULL; | 
 |         tmp = BinOp(e, Pow, f, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         if (!tmp) | 
 |             return NULL; | 
 |         e = tmp; | 
 |     } | 
 |     return e; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_starred(struct compiling *c, const node *n) | 
 | { | 
 |     expr_ty tmp; | 
 |     REQ(n, star_expr); | 
 |  | 
 |     tmp = ast_for_expr(c, CHILD(n, 1)); | 
 |     if (!tmp) | 
 |         return NULL; | 
 |  | 
 |     /* The Load context is changed later. */ | 
 |     return Starred(tmp, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 |  | 
 | /* Do not name a variable 'expr'!  Will cause a compile error. | 
 | */ | 
 |  | 
 | static expr_ty | 
 | ast_for_expr(struct compiling *c, const node *n) | 
 | { | 
 |     /* handle the full range of simple expressions | 
 |        test: or_test ['if' or_test 'else' test] | lambdef | 
 |        test_nocond: or_test | lambdef_nocond | 
 |        or_test: and_test ('or' and_test)* | 
 |        and_test: not_test ('and' not_test)* | 
 |        not_test: 'not' not_test | comparison | 
 |        comparison: expr (comp_op expr)* | 
 |        expr: xor_expr ('|' xor_expr)* | 
 |        xor_expr: and_expr ('^' and_expr)* | 
 |        and_expr: shift_expr ('&' shift_expr)* | 
 |        shift_expr: arith_expr (('<<'|'>>') arith_expr)* | 
 |        arith_expr: term (('+'|'-') term)* | 
 |        term: factor (('*'|'/'|'%'|'//') factor)* | 
 |        factor: ('+'|'-'|'~') factor | power | 
 |        power: atom trailer* ('**' factor)* | 
 |     */ | 
 |  | 
 |     asdl_seq *seq; | 
 |     int i; | 
 |  | 
 |  loop: | 
 |     switch (TYPE(n)) { | 
 |         case test: | 
 |         case test_nocond: | 
 |             if (TYPE(CHILD(n, 0)) == lambdef || | 
 |                 TYPE(CHILD(n, 0)) == lambdef_nocond) | 
 |                 return ast_for_lambdef(c, CHILD(n, 0)); | 
 |             else if (NCH(n) > 1) | 
 |                 return ast_for_ifexpr(c, n); | 
 |             /* Fallthrough */ | 
 |         case or_test: | 
 |         case and_test: | 
 |             if (NCH(n) == 1) { | 
 |                 n = CHILD(n, 0); | 
 |                 goto loop; | 
 |             } | 
 |             seq = asdl_seq_new((NCH(n) + 1) / 2, c->c_arena); | 
 |             if (!seq) | 
 |                 return NULL; | 
 |             for (i = 0; i < NCH(n); i += 2) { | 
 |                 expr_ty e = ast_for_expr(c, CHILD(n, i)); | 
 |                 if (!e) | 
 |                     return NULL; | 
 |                 asdl_seq_SET(seq, i / 2, e); | 
 |             } | 
 |             if (!strcmp(STR(CHILD(n, 1)), "and")) | 
 |                 return BoolOp(And, seq, LINENO(n), n->n_col_offset, | 
 |                               c->c_arena); | 
 |             assert(!strcmp(STR(CHILD(n, 1)), "or")); | 
 |             return BoolOp(Or, seq, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         case not_test: | 
 |             if (NCH(n) == 1) { | 
 |                 n = CHILD(n, 0); | 
 |                 goto loop; | 
 |             } | 
 |             else { | 
 |                 expr_ty expression = ast_for_expr(c, CHILD(n, 1)); | 
 |                 if (!expression) | 
 |                     return NULL; | 
 |  | 
 |                 return UnaryOp(Not, expression, LINENO(n), n->n_col_offset, | 
 |                                c->c_arena); | 
 |             } | 
 |         case comparison: | 
 |             if (NCH(n) == 1) { | 
 |                 n = CHILD(n, 0); | 
 |                 goto loop; | 
 |             } | 
 |             else { | 
 |                 expr_ty expression; | 
 |                 asdl_int_seq *ops; | 
 |                 asdl_seq *cmps; | 
 |                 ops = asdl_int_seq_new(NCH(n) / 2, c->c_arena); | 
 |                 if (!ops) | 
 |                     return NULL; | 
 |                 cmps = asdl_seq_new(NCH(n) / 2, c->c_arena); | 
 |                 if (!cmps) { | 
 |                     return NULL; | 
 |                 } | 
 |                 for (i = 1; i < NCH(n); i += 2) { | 
 |                     cmpop_ty newoperator; | 
 |  | 
 |                     newoperator = ast_for_comp_op(c, CHILD(n, i)); | 
 |                     if (!newoperator) { | 
 |                         return NULL; | 
 |                     } | 
 |  | 
 |                     expression = ast_for_expr(c, CHILD(n, i + 1)); | 
 |                     if (!expression) { | 
 |                         return NULL; | 
 |                     } | 
 |  | 
 |                     asdl_seq_SET(ops, i / 2, newoperator); | 
 |                     asdl_seq_SET(cmps, i / 2, expression); | 
 |                 } | 
 |                 expression = ast_for_expr(c, CHILD(n, 0)); | 
 |                 if (!expression) { | 
 |                     return NULL; | 
 |                 } | 
 |  | 
 |                 return Compare(expression, ops, cmps, LINENO(n), | 
 |                                n->n_col_offset, c->c_arena); | 
 |             } | 
 |             break; | 
 |  | 
 |         case star_expr: | 
 |             return ast_for_starred(c, n); | 
 |         /* The next five cases all handle BinOps.  The main body of code | 
 |            is the same in each case, but the switch turned inside out to | 
 |            reuse the code for each type of operator. | 
 |          */ | 
 |         case expr: | 
 |         case xor_expr: | 
 |         case and_expr: | 
 |         case shift_expr: | 
 |         case arith_expr: | 
 |         case term: | 
 |             if (NCH(n) == 1) { | 
 |                 n = CHILD(n, 0); | 
 |                 goto loop; | 
 |             } | 
 |             return ast_for_binop(c, n); | 
 |         case yield_expr: { | 
 |             expr_ty exp = NULL; | 
 |             if (NCH(n) == 2) { | 
 |                 exp = ast_for_testlist(c, CHILD(n, 1)); | 
 |                 if (!exp) | 
 |                     return NULL; | 
 |             } | 
 |             return Yield(exp, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         } | 
 |         case factor: | 
 |             if (NCH(n) == 1) { | 
 |                 n = CHILD(n, 0); | 
 |                 goto loop; | 
 |             } | 
 |             return ast_for_factor(c, n); | 
 |         case power: | 
 |             return ast_for_power(c, n); | 
 |         default: | 
 |             PyErr_Format(PyExc_SystemError, "unhandled expr: %d", TYPE(n)); | 
 |             return NULL; | 
 |     } | 
 |     /* should never get here unless if error is set */ | 
 |     return NULL; | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_call(struct compiling *c, const node *n, expr_ty func) | 
 | { | 
 |     /* | 
 |       arglist: (argument ',')* (argument [',']| '*' test [',' '**' test] | 
 |                | '**' test) | 
 |       argument: [test '='] test [comp_for]        # Really [keyword '='] test | 
 |     */ | 
 |  | 
 |     int i, nargs, nkeywords, ngens; | 
 |     asdl_seq *args; | 
 |     asdl_seq *keywords; | 
 |     expr_ty vararg = NULL, kwarg = NULL; | 
 |  | 
 |     REQ(n, arglist); | 
 |  | 
 |     nargs = 0; | 
 |     nkeywords = 0; | 
 |     ngens = 0; | 
 |     for (i = 0; i < NCH(n); i++) { | 
 |         node *ch = CHILD(n, i); | 
 |         if (TYPE(ch) == argument) { | 
 |             if (NCH(ch) == 1) | 
 |                 nargs++; | 
 |             else if (TYPE(CHILD(ch, 1)) == comp_for) | 
 |                 ngens++; | 
 |             else | 
 |                 nkeywords++; | 
 |         } | 
 |     } | 
 |     if (ngens > 1 || (ngens && (nargs || nkeywords))) { | 
 |         ast_error(n, "Generator expression must be parenthesized " | 
 |                   "if not sole argument"); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (nargs + nkeywords + ngens > 255) { | 
 |       ast_error(n, "more than 255 arguments"); | 
 |       return NULL; | 
 |     } | 
 |  | 
 |     args = asdl_seq_new(nargs + ngens, c->c_arena); | 
 |     if (!args) | 
 |         return NULL; | 
 |     keywords = asdl_seq_new(nkeywords, c->c_arena); | 
 |     if (!keywords) | 
 |         return NULL; | 
 |     nargs = 0; | 
 |     nkeywords = 0; | 
 |     for (i = 0; i < NCH(n); i++) { | 
 |         node *ch = CHILD(n, i); | 
 |         if (TYPE(ch) == argument) { | 
 |             expr_ty e; | 
 |             if (NCH(ch) == 1) { | 
 |                 if (nkeywords) { | 
 |                     ast_error(CHILD(ch, 0), | 
 |                               "non-keyword arg after keyword arg"); | 
 |                     return NULL; | 
 |                 } | 
 |                 if (vararg) { | 
 |                     ast_error(CHILD(ch, 0), | 
 |                               "only named arguments may follow *expression"); | 
 |                     return NULL; | 
 |                 } | 
 |                 e = ast_for_expr(c, CHILD(ch, 0)); | 
 |                 if (!e) | 
 |                     return NULL; | 
 |                 asdl_seq_SET(args, nargs++, e); | 
 |             } | 
 |             else if (TYPE(CHILD(ch, 1)) == comp_for) { | 
 |                 e = ast_for_genexp(c, ch); | 
 |                 if (!e) | 
 |                     return NULL; | 
 |                 asdl_seq_SET(args, nargs++, e); | 
 |             } | 
 |             else { | 
 |                 keyword_ty kw; | 
 |                 identifier key, tmp; | 
 |                 int k; | 
 |  | 
 |                 /* CHILD(ch, 0) is test, but must be an identifier? */ | 
 |                 e = ast_for_expr(c, CHILD(ch, 0)); | 
 |                 if (!e) | 
 |                     return NULL; | 
 |                 /* f(lambda x: x[0] = 3) ends up getting parsed with | 
 |                  * LHS test = lambda x: x[0], and RHS test = 3. | 
 |                  * SF bug 132313 points out that complaining about a keyword | 
 |                  * then is very confusing. | 
 |                  */ | 
 |                 if (e->kind == Lambda_kind) { | 
 |                   ast_error(CHILD(ch, 0), "lambda cannot contain assignment"); | 
 |                   return NULL; | 
 |                 } else if (e->kind != Name_kind) { | 
 |                   ast_error(CHILD(ch, 0), "keyword can't be an expression"); | 
 |                   return NULL; | 
 |                 } else if (forbidden_name(e->v.Name.id, ch, 1)) { | 
 |                   return NULL; | 
 |                 } | 
 |                 key = e->v.Name.id; | 
 |                 for (k = 0; k < nkeywords; k++) { | 
 |                     tmp = ((keyword_ty)asdl_seq_GET(keywords, k))->arg; | 
 |                     if (!PyUnicode_Compare(tmp, key)) { | 
 |                         ast_error(CHILD(ch, 0), "keyword argument repeated"); | 
 |                         return NULL; | 
 |                     } | 
 |                 } | 
 |                 e = ast_for_expr(c, CHILD(ch, 2)); | 
 |                 if (!e) | 
 |                     return NULL; | 
 |                 kw = keyword(key, e, c->c_arena); | 
 |                 if (!kw) | 
 |                     return NULL; | 
 |                 asdl_seq_SET(keywords, nkeywords++, kw); | 
 |             } | 
 |         } | 
 |         else if (TYPE(ch) == STAR) { | 
 |             vararg = ast_for_expr(c, CHILD(n, i+1)); | 
 |             if (!vararg) | 
 |                 return NULL; | 
 |             i++; | 
 |         } | 
 |         else if (TYPE(ch) == DOUBLESTAR) { | 
 |             kwarg = ast_for_expr(c, CHILD(n, i+1)); | 
 |             if (!kwarg) | 
 |                 return NULL; | 
 |             i++; | 
 |         } | 
 |     } | 
 |  | 
 |     return Call(func, args, keywords, vararg, kwarg, func->lineno, func->col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static expr_ty | 
 | ast_for_testlist(struct compiling *c, const node* n) | 
 | { | 
 |     /* testlist_comp: test (comp_for | (',' test)* [',']) */ | 
 |     /* testlist: test (',' test)* [','] */ | 
 |     assert(NCH(n) > 0); | 
 |     if (TYPE(n) == testlist_comp) { | 
 |         if (NCH(n) > 1) | 
 |             assert(TYPE(CHILD(n, 1)) != comp_for); | 
 |     } | 
 |     else { | 
 |         assert(TYPE(n) == testlist || | 
 |                TYPE(n) == testlist_star_expr); | 
 |     } | 
 |     if (NCH(n) == 1) | 
 |         return ast_for_expr(c, CHILD(n, 0)); | 
 |     else { | 
 |         asdl_seq *tmp = seq_for_testlist(c, n); | 
 |         if (!tmp) | 
 |             return NULL; | 
 |         return Tuple(tmp, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_expr_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     REQ(n, expr_stmt); | 
 |     /* expr_stmt: testlist_star_expr (augassign (yield_expr|testlist) | 
 |                 | ('=' (yield_expr|testlist))*) | 
 |        testlist_star_expr: (test|star_expr) (',' test|star_expr)* [','] | 
 |        augassign: '+=' | '-=' | '*=' | '/=' | '%=' | '&=' | '|=' | '^=' | 
 |                 | '<<=' | '>>=' | '**=' | '//=' | 
 |        test: ... here starts the operator precendence dance | 
 |      */ | 
 |  | 
 |     if (NCH(n) == 1) { | 
 |         expr_ty e = ast_for_testlist(c, CHILD(n, 0)); | 
 |         if (!e) | 
 |             return NULL; | 
 |  | 
 |         return Expr(e, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     else if (TYPE(CHILD(n, 1)) == augassign) { | 
 |         expr_ty expr1, expr2; | 
 |         operator_ty newoperator; | 
 |         node *ch = CHILD(n, 0); | 
 |  | 
 |         expr1 = ast_for_testlist(c, ch); | 
 |         if (!expr1) | 
 |             return NULL; | 
 |         if(!set_context(c, expr1, Store, ch)) | 
 |             return NULL; | 
 |         /* set_context checks that most expressions are not the left side. | 
 |           Augmented assignments can only have a name, a subscript, or an | 
 |           attribute on the left, though, so we have to explicitly check for | 
 |           those. */ | 
 |         switch (expr1->kind) { | 
 |             case Name_kind: | 
 |             case Attribute_kind: | 
 |             case Subscript_kind: | 
 |                 break; | 
 |             default: | 
 |                 ast_error(ch, "illegal expression for augmented assignment"); | 
 |                 return NULL; | 
 |         } | 
 |  | 
 |         ch = CHILD(n, 2); | 
 |         if (TYPE(ch) == testlist) | 
 |             expr2 = ast_for_testlist(c, ch); | 
 |         else | 
 |             expr2 = ast_for_expr(c, ch); | 
 |         if (!expr2) | 
 |             return NULL; | 
 |  | 
 |         newoperator = ast_for_augassign(c, CHILD(n, 1)); | 
 |         if (!newoperator) | 
 |             return NULL; | 
 |  | 
 |         return AugAssign(expr1, newoperator, expr2, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     else { | 
 |         int i; | 
 |         asdl_seq *targets; | 
 |         node *value; | 
 |         expr_ty expression; | 
 |  | 
 |         /* a normal assignment */ | 
 |         REQ(CHILD(n, 1), EQUAL); | 
 |         targets = asdl_seq_new(NCH(n) / 2, c->c_arena); | 
 |         if (!targets) | 
 |             return NULL; | 
 |         for (i = 0; i < NCH(n) - 2; i += 2) { | 
 |             expr_ty e; | 
 |             node *ch = CHILD(n, i); | 
 |             if (TYPE(ch) == yield_expr) { | 
 |                 ast_error(ch, "assignment to yield expression not possible"); | 
 |                 return NULL; | 
 |             } | 
 |             e = ast_for_testlist(c, ch); | 
 |  | 
 |             /* set context to assign */ | 
 |             if (!e) | 
 |               return NULL; | 
 |  | 
 |             if (!set_context(c, e, Store, CHILD(n, i))) | 
 |               return NULL; | 
 |  | 
 |             asdl_seq_SET(targets, i / 2, e); | 
 |         } | 
 |         value = CHILD(n, NCH(n) - 1); | 
 |         if (TYPE(value) == testlist_star_expr) | 
 |             expression = ast_for_testlist(c, value); | 
 |         else | 
 |             expression = ast_for_expr(c, value); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         return Assign(targets, expression, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 | } | 
 |  | 
 |  | 
 | static asdl_seq * | 
 | ast_for_exprlist(struct compiling *c, const node *n, expr_context_ty context) | 
 | { | 
 |     asdl_seq *seq; | 
 |     int i; | 
 |     expr_ty e; | 
 |  | 
 |     REQ(n, exprlist); | 
 |  | 
 |     seq = asdl_seq_new((NCH(n) + 1) / 2, c->c_arena); | 
 |     if (!seq) | 
 |         return NULL; | 
 |     for (i = 0; i < NCH(n); i += 2) { | 
 |         e = ast_for_expr(c, CHILD(n, i)); | 
 |         if (!e) | 
 |             return NULL; | 
 |         asdl_seq_SET(seq, i / 2, e); | 
 |         if (context && !set_context(c, e, context, CHILD(n, i))) | 
 |             return NULL; | 
 |     } | 
 |     return seq; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_del_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     asdl_seq *expr_list; | 
 |  | 
 |     /* del_stmt: 'del' exprlist */ | 
 |     REQ(n, del_stmt); | 
 |  | 
 |     expr_list = ast_for_exprlist(c, CHILD(n, 1), Del); | 
 |     if (!expr_list) | 
 |         return NULL; | 
 |     return Delete(expr_list, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_flow_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     /* | 
 |       flow_stmt: break_stmt | continue_stmt | return_stmt | raise_stmt | 
 |                  | yield_stmt | 
 |       break_stmt: 'break' | 
 |       continue_stmt: 'continue' | 
 |       return_stmt: 'return' [testlist] | 
 |       yield_stmt: yield_expr | 
 |       yield_expr: 'yield' testlist | 
 |       raise_stmt: 'raise' [test [',' test [',' test]]] | 
 |     */ | 
 |     node *ch; | 
 |  | 
 |     REQ(n, flow_stmt); | 
 |     ch = CHILD(n, 0); | 
 |     switch (TYPE(ch)) { | 
 |         case break_stmt: | 
 |             return Break(LINENO(n), n->n_col_offset, c->c_arena); | 
 |         case continue_stmt: | 
 |             return Continue(LINENO(n), n->n_col_offset, c->c_arena); | 
 |         case yield_stmt: { /* will reduce to yield_expr */ | 
 |             expr_ty exp = ast_for_expr(c, CHILD(ch, 0)); | 
 |             if (!exp) | 
 |                 return NULL; | 
 |             return Expr(exp, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         } | 
 |         case return_stmt: | 
 |             if (NCH(ch) == 1) | 
 |                 return Return(NULL, LINENO(n), n->n_col_offset, c->c_arena); | 
 |             else { | 
 |                 expr_ty expression = ast_for_testlist(c, CHILD(ch, 1)); | 
 |                 if (!expression) | 
 |                     return NULL; | 
 |                 return Return(expression, LINENO(n), n->n_col_offset, c->c_arena); | 
 |             } | 
 |         case raise_stmt: | 
 |             if (NCH(ch) == 1) | 
 |                 return Raise(NULL, NULL, LINENO(n), n->n_col_offset, c->c_arena); | 
 |             else if (NCH(ch) >= 2) { | 
 |                 expr_ty cause = NULL; | 
 |                 expr_ty expression = ast_for_expr(c, CHILD(ch, 1)); | 
 |                 if (!expression) | 
 |                     return NULL; | 
 |                 if (NCH(ch) == 4) { | 
 |                     cause = ast_for_expr(c, CHILD(ch, 3)); | 
 |                     if (!cause) | 
 |                         return NULL; | 
 |                 } | 
 |                 return Raise(expression, cause, LINENO(n), n->n_col_offset, c->c_arena); | 
 |             } | 
 |         default: | 
 |             PyErr_Format(PyExc_SystemError, | 
 |                          "unexpected flow_stmt: %d", TYPE(ch)); | 
 |             return NULL; | 
 |     } | 
 |  | 
 |     PyErr_SetString(PyExc_SystemError, "unhandled flow statement"); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static alias_ty | 
 | alias_for_import_name(struct compiling *c, const node *n, int store) | 
 | { | 
 |     /* | 
 |       import_as_name: NAME ['as' NAME] | 
 |       dotted_as_name: dotted_name ['as' NAME] | 
 |       dotted_name: NAME ('.' NAME)* | 
 |     */ | 
 |     identifier str, name; | 
 |  | 
 |  loop: | 
 |     switch (TYPE(n)) { | 
 |          case import_as_name: { | 
 |             node *name_node = CHILD(n, 0); | 
 |             str = NULL; | 
 |             name = NEW_IDENTIFIER(name_node); | 
 |             if (!name) | 
 |                 return NULL; | 
 |             if (NCH(n) == 3) { | 
 |                 node *str_node = CHILD(n, 2); | 
 |                 str = NEW_IDENTIFIER(str_node); | 
 |                 if (!str) | 
 |                     return NULL; | 
 |                 if (store && forbidden_name(str, str_node, 0)) | 
 |                     return NULL; | 
 |             } | 
 |             else { | 
 |                 if (forbidden_name(name, name_node, 0)) | 
 |                     return NULL; | 
 |             } | 
 |             return alias(name, str, c->c_arena); | 
 |         } | 
 |         case dotted_as_name: | 
 |             if (NCH(n) == 1) { | 
 |                 n = CHILD(n, 0); | 
 |                 goto loop; | 
 |             } | 
 |             else { | 
 |                 node *asname_node = CHILD(n, 2); | 
 |                 alias_ty a = alias_for_import_name(c, CHILD(n, 0), 0); | 
 |                 if (!a) | 
 |                     return NULL; | 
 |                 assert(!a->asname); | 
 |                 a->asname = NEW_IDENTIFIER(asname_node); | 
 |                 if (!a->asname) | 
 |                     return NULL; | 
 |                 if (forbidden_name(a->asname, asname_node, 0)) | 
 |                     return NULL; | 
 |                 return a; | 
 |             } | 
 |             break; | 
 |         case dotted_name: | 
 |             if (NCH(n) == 1) { | 
 |                 node *name_node = CHILD(n, 0); | 
 |                 name = NEW_IDENTIFIER(name_node); | 
 |                 if (!name) | 
 |                     return NULL; | 
 |                 if (store && forbidden_name(name, name_node, 0)) | 
 |                     return NULL; | 
 |                 return alias(name, NULL, c->c_arena); | 
 |             } | 
 |             else { | 
 |                 /* Create a string of the form "a.b.c" */ | 
 |                 int i; | 
 |                 size_t len; | 
 |                 char *s; | 
 |                 PyObject *uni; | 
 |  | 
 |                 len = 0; | 
 |                 for (i = 0; i < NCH(n); i += 2) | 
 |                     /* length of string plus one for the dot */ | 
 |                     len += strlen(STR(CHILD(n, i))) + 1; | 
 |                 len--; /* the last name doesn't have a dot */ | 
 |                 str = PyBytes_FromStringAndSize(NULL, len); | 
 |                 if (!str) | 
 |                     return NULL; | 
 |                 s = PyBytes_AS_STRING(str); | 
 |                 if (!s) | 
 |                     return NULL; | 
 |                 for (i = 0; i < NCH(n); i += 2) { | 
 |                     char *sch = STR(CHILD(n, i)); | 
 |                     strcpy(s, STR(CHILD(n, i))); | 
 |                     s += strlen(sch); | 
 |                     *s++ = '.'; | 
 |                 } | 
 |                 --s; | 
 |                 *s = '\0'; | 
 |                 uni = PyUnicode_DecodeUTF8(PyBytes_AS_STRING(str), | 
 |                                            PyBytes_GET_SIZE(str), | 
 |                                            NULL); | 
 |                 Py_DECREF(str); | 
 |                 if (!uni) | 
 |                     return NULL; | 
 |                 str = uni; | 
 |                 PyUnicode_InternInPlace(&str); | 
 |                 PyArena_AddPyObject(c->c_arena, str); | 
 |                 return alias(str, NULL, c->c_arena); | 
 |             } | 
 |             break; | 
 |         case STAR: | 
 |             str = PyUnicode_InternFromString("*"); | 
 |             PyArena_AddPyObject(c->c_arena, str); | 
 |             return alias(str, NULL, c->c_arena); | 
 |         default: | 
 |             PyErr_Format(PyExc_SystemError, | 
 |                          "unexpected import name: %d", TYPE(n)); | 
 |             return NULL; | 
 |     } | 
 |  | 
 |     PyErr_SetString(PyExc_SystemError, "unhandled import name condition"); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_import_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     /* | 
 |       import_stmt: import_name | import_from | 
 |       import_name: 'import' dotted_as_names | 
 |       import_from: 'from' (('.' | '...')* dotted_name | ('.' | '...')+) | 
 |                    'import' ('*' | '(' import_as_names ')' | import_as_names) | 
 |     */ | 
 |     int lineno; | 
 |     int col_offset; | 
 |     int i; | 
 |     asdl_seq *aliases; | 
 |  | 
 |     REQ(n, import_stmt); | 
 |     lineno = LINENO(n); | 
 |     col_offset = n->n_col_offset; | 
 |     n = CHILD(n, 0); | 
 |     if (TYPE(n) == import_name) { | 
 |         n = CHILD(n, 1); | 
 |         REQ(n, dotted_as_names); | 
 |         aliases = asdl_seq_new((NCH(n) + 1) / 2, c->c_arena); | 
 |         if (!aliases) | 
 |                 return NULL; | 
 |         for (i = 0; i < NCH(n); i += 2) { | 
 |             alias_ty import_alias = alias_for_import_name(c, CHILD(n, i), 1); | 
 |             if (!import_alias) | 
 |                 return NULL; | 
 |             asdl_seq_SET(aliases, i / 2, import_alias); | 
 |         } | 
 |         return Import(aliases, lineno, col_offset, c->c_arena); | 
 |     } | 
 |     else if (TYPE(n) == import_from) { | 
 |         int n_children; | 
 |         int idx, ndots = 0; | 
 |         alias_ty mod = NULL; | 
 |         identifier modname = NULL; | 
 |  | 
 |        /* Count the number of dots (for relative imports) and check for the | 
 |           optional module name */ | 
 |         for (idx = 1; idx < NCH(n); idx++) { | 
 |             if (TYPE(CHILD(n, idx)) == dotted_name) { | 
 |                 mod = alias_for_import_name(c, CHILD(n, idx), 0); | 
 |                 if (!mod) | 
 |                     return NULL; | 
 |                 idx++; | 
 |                 break; | 
 |             } else if (TYPE(CHILD(n, idx)) == ELLIPSIS) { | 
 |                 /* three consecutive dots are tokenized as one ELLIPSIS */ | 
 |                 ndots += 3; | 
 |                 continue; | 
 |             } else if (TYPE(CHILD(n, idx)) != DOT) { | 
 |                 break; | 
 |             } | 
 |             ndots++; | 
 |         } | 
 |         idx++; /* skip over the 'import' keyword */ | 
 |         switch (TYPE(CHILD(n, idx))) { | 
 |         case STAR: | 
 |             /* from ... import * */ | 
 |             n = CHILD(n, idx); | 
 |             n_children = 1; | 
 |             break; | 
 |         case LPAR: | 
 |             /* from ... import (x, y, z) */ | 
 |             n = CHILD(n, idx + 1); | 
 |             n_children = NCH(n); | 
 |             break; | 
 |         case import_as_names: | 
 |             /* from ... import x, y, z */ | 
 |             n = CHILD(n, idx); | 
 |             n_children = NCH(n); | 
 |             if (n_children % 2 == 0) { | 
 |                 ast_error(n, "trailing comma not allowed without" | 
 |                              " surrounding parentheses"); | 
 |                 return NULL; | 
 |             } | 
 |             break; | 
 |         default: | 
 |             ast_error(n, "Unexpected node-type in from-import"); | 
 |             return NULL; | 
 |         } | 
 |  | 
 |         aliases = asdl_seq_new((n_children + 1) / 2, c->c_arena); | 
 |         if (!aliases) | 
 |             return NULL; | 
 |  | 
 |         /* handle "from ... import *" special b/c there's no children */ | 
 |         if (TYPE(n) == STAR) { | 
 |             alias_ty import_alias = alias_for_import_name(c, n, 1); | 
 |             if (!import_alias) | 
 |                 return NULL; | 
 |                 asdl_seq_SET(aliases, 0, import_alias); | 
 |         } | 
 |         else { | 
 |             for (i = 0; i < NCH(n); i += 2) { | 
 |                 alias_ty import_alias = alias_for_import_name(c, CHILD(n, i), 1); | 
 |                 if (!import_alias) | 
 |                     return NULL; | 
 |                     asdl_seq_SET(aliases, i / 2, import_alias); | 
 |             } | 
 |         } | 
 |         if (mod != NULL) | 
 |             modname = mod->name; | 
 |         return ImportFrom(modname, aliases, ndots, lineno, col_offset, | 
 |                           c->c_arena); | 
 |     } | 
 |     PyErr_Format(PyExc_SystemError, | 
 |                  "unknown import statement: starts with command '%s'", | 
 |                  STR(CHILD(n, 0))); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_global_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     /* global_stmt: 'global' NAME (',' NAME)* */ | 
 |     identifier name; | 
 |     asdl_seq *s; | 
 |     int i; | 
 |  | 
 |     REQ(n, global_stmt); | 
 |     s = asdl_seq_new(NCH(n) / 2, c->c_arena); | 
 |     if (!s) | 
 |         return NULL; | 
 |     for (i = 1; i < NCH(n); i += 2) { | 
 |         name = NEW_IDENTIFIER(CHILD(n, i)); | 
 |         if (!name) | 
 |             return NULL; | 
 |         asdl_seq_SET(s, i / 2, name); | 
 |     } | 
 |     return Global(s, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_nonlocal_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     /* nonlocal_stmt: 'nonlocal' NAME (',' NAME)* */ | 
 |     identifier name; | 
 |     asdl_seq *s; | 
 |     int i; | 
 |  | 
 |     REQ(n, nonlocal_stmt); | 
 |     s = asdl_seq_new(NCH(n) / 2, c->c_arena); | 
 |     if (!s) | 
 |         return NULL; | 
 |     for (i = 1; i < NCH(n); i += 2) { | 
 |         name = NEW_IDENTIFIER(CHILD(n, i)); | 
 |         if (!name) | 
 |             return NULL; | 
 |         asdl_seq_SET(s, i / 2, name); | 
 |     } | 
 |     return Nonlocal(s, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_assert_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     /* assert_stmt: 'assert' test [',' test] */ | 
 |     REQ(n, assert_stmt); | 
 |     if (NCH(n) == 2) { | 
 |         expr_ty expression = ast_for_expr(c, CHILD(n, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         return Assert(expression, NULL, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     else if (NCH(n) == 4) { | 
 |         expr_ty expr1, expr2; | 
 |  | 
 |         expr1 = ast_for_expr(c, CHILD(n, 1)); | 
 |         if (!expr1) | 
 |             return NULL; | 
 |         expr2 = ast_for_expr(c, CHILD(n, 3)); | 
 |         if (!expr2) | 
 |             return NULL; | 
 |  | 
 |         return Assert(expr1, expr2, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     PyErr_Format(PyExc_SystemError, | 
 |                  "improper number of parts to 'assert' statement: %d", | 
 |                  NCH(n)); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static asdl_seq * | 
 | ast_for_suite(struct compiling *c, const node *n) | 
 | { | 
 |     /* suite: simple_stmt | NEWLINE INDENT stmt+ DEDENT */ | 
 |     asdl_seq *seq; | 
 |     stmt_ty s; | 
 |     int i, total, num, end, pos = 0; | 
 |     node *ch; | 
 |  | 
 |     REQ(n, suite); | 
 |  | 
 |     total = num_stmts(n); | 
 |     seq = asdl_seq_new(total, c->c_arena); | 
 |     if (!seq) | 
 |         return NULL; | 
 |     if (TYPE(CHILD(n, 0)) == simple_stmt) { | 
 |         n = CHILD(n, 0); | 
 |         /* simple_stmt always ends with a NEWLINE, | 
 |            and may have a trailing SEMI | 
 |         */ | 
 |         end = NCH(n) - 1; | 
 |         if (TYPE(CHILD(n, end - 1)) == SEMI) | 
 |             end--; | 
 |         /* loop by 2 to skip semi-colons */ | 
 |         for (i = 0; i < end; i += 2) { | 
 |             ch = CHILD(n, i); | 
 |             s = ast_for_stmt(c, ch); | 
 |             if (!s) | 
 |                 return NULL; | 
 |             asdl_seq_SET(seq, pos++, s); | 
 |         } | 
 |     } | 
 |     else { | 
 |         for (i = 2; i < (NCH(n) - 1); i++) { | 
 |             ch = CHILD(n, i); | 
 |             REQ(ch, stmt); | 
 |             num = num_stmts(ch); | 
 |             if (num == 1) { | 
 |                 /* small_stmt or compound_stmt with only one child */ | 
 |                 s = ast_for_stmt(c, ch); | 
 |                 if (!s) | 
 |                     return NULL; | 
 |                 asdl_seq_SET(seq, pos++, s); | 
 |             } | 
 |             else { | 
 |                 int j; | 
 |                 ch = CHILD(ch, 0); | 
 |                 REQ(ch, simple_stmt); | 
 |                 for (j = 0; j < NCH(ch); j += 2) { | 
 |                     /* statement terminates with a semi-colon ';' */ | 
 |                     if (NCH(CHILD(ch, j)) == 0) { | 
 |                         assert((j + 1) == NCH(ch)); | 
 |                         break; | 
 |                     } | 
 |                     s = ast_for_stmt(c, CHILD(ch, j)); | 
 |                     if (!s) | 
 |                         return NULL; | 
 |                     asdl_seq_SET(seq, pos++, s); | 
 |                 } | 
 |             } | 
 |         } | 
 |     } | 
 |     assert(pos == seq->size); | 
 |     return seq; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_if_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     /* if_stmt: 'if' test ':' suite ('elif' test ':' suite)* | 
 |        ['else' ':' suite] | 
 |     */ | 
 |     char *s; | 
 |  | 
 |     REQ(n, if_stmt); | 
 |  | 
 |     if (NCH(n) == 4) { | 
 |         expr_ty expression; | 
 |         asdl_seq *suite_seq; | 
 |  | 
 |         expression = ast_for_expr(c, CHILD(n, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         suite_seq = ast_for_suite(c, CHILD(n, 3)); | 
 |         if (!suite_seq) | 
 |             return NULL; | 
 |  | 
 |         return If(expression, suite_seq, NULL, LINENO(n), n->n_col_offset, | 
 |                   c->c_arena); | 
 |     } | 
 |  | 
 |     s = STR(CHILD(n, 4)); | 
 |     /* s[2], the third character in the string, will be | 
 |        's' for el_s_e, or | 
 |        'i' for el_i_f | 
 |     */ | 
 |     if (s[2] == 's') { | 
 |         expr_ty expression; | 
 |         asdl_seq *seq1, *seq2; | 
 |  | 
 |         expression = ast_for_expr(c, CHILD(n, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         seq1 = ast_for_suite(c, CHILD(n, 3)); | 
 |         if (!seq1) | 
 |             return NULL; | 
 |         seq2 = ast_for_suite(c, CHILD(n, 6)); | 
 |         if (!seq2) | 
 |             return NULL; | 
 |  | 
 |         return If(expression, seq1, seq2, LINENO(n), n->n_col_offset, | 
 |                   c->c_arena); | 
 |     } | 
 |     else if (s[2] == 'i') { | 
 |         int i, n_elif, has_else = 0; | 
 |         expr_ty expression; | 
 |         asdl_seq *suite_seq; | 
 |         asdl_seq *orelse = NULL; | 
 |         n_elif = NCH(n) - 4; | 
 |         /* must reference the child n_elif+1 since 'else' token is third, | 
 |            not fourth, child from the end. */ | 
 |         if (TYPE(CHILD(n, (n_elif + 1))) == NAME | 
 |             && STR(CHILD(n, (n_elif + 1)))[2] == 's') { | 
 |             has_else = 1; | 
 |             n_elif -= 3; | 
 |         } | 
 |         n_elif /= 4; | 
 |  | 
 |         if (has_else) { | 
 |             asdl_seq *suite_seq2; | 
 |  | 
 |             orelse = asdl_seq_new(1, c->c_arena); | 
 |             if (!orelse) | 
 |                 return NULL; | 
 |             expression = ast_for_expr(c, CHILD(n, NCH(n) - 6)); | 
 |             if (!expression) | 
 |                 return NULL; | 
 |             suite_seq = ast_for_suite(c, CHILD(n, NCH(n) - 4)); | 
 |             if (!suite_seq) | 
 |                 return NULL; | 
 |             suite_seq2 = ast_for_suite(c, CHILD(n, NCH(n) - 1)); | 
 |             if (!suite_seq2) | 
 |                 return NULL; | 
 |  | 
 |             asdl_seq_SET(orelse, 0, | 
 |                          If(expression, suite_seq, suite_seq2, | 
 |                             LINENO(CHILD(n, NCH(n) - 6)), | 
 |                             CHILD(n, NCH(n) - 6)->n_col_offset, | 
 |                             c->c_arena)); | 
 |             /* the just-created orelse handled the last elif */ | 
 |             n_elif--; | 
 |         } | 
 |  | 
 |         for (i = 0; i < n_elif; i++) { | 
 |             int off = 5 + (n_elif - i - 1) * 4; | 
 |             asdl_seq *newobj = asdl_seq_new(1, c->c_arena); | 
 |             if (!newobj) | 
 |                 return NULL; | 
 |             expression = ast_for_expr(c, CHILD(n, off)); | 
 |             if (!expression) | 
 |                 return NULL; | 
 |             suite_seq = ast_for_suite(c, CHILD(n, off + 2)); | 
 |             if (!suite_seq) | 
 |                 return NULL; | 
 |  | 
 |             asdl_seq_SET(newobj, 0, | 
 |                          If(expression, suite_seq, orelse, | 
 |                             LINENO(CHILD(n, off)), | 
 |                             CHILD(n, off)->n_col_offset, c->c_arena)); | 
 |             orelse = newobj; | 
 |         } | 
 |         expression = ast_for_expr(c, CHILD(n, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         suite_seq = ast_for_suite(c, CHILD(n, 3)); | 
 |         if (!suite_seq) | 
 |             return NULL; | 
 |         return If(expression, suite_seq, orelse, | 
 |                   LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |  | 
 |     PyErr_Format(PyExc_SystemError, | 
 |                  "unexpected token in 'if' statement: %s", s); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_while_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     /* while_stmt: 'while' test ':' suite ['else' ':' suite] */ | 
 |     REQ(n, while_stmt); | 
 |  | 
 |     if (NCH(n) == 4) { | 
 |         expr_ty expression; | 
 |         asdl_seq *suite_seq; | 
 |  | 
 |         expression = ast_for_expr(c, CHILD(n, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         suite_seq = ast_for_suite(c, CHILD(n, 3)); | 
 |         if (!suite_seq) | 
 |             return NULL; | 
 |         return While(expression, suite_seq, NULL, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |     else if (NCH(n) == 7) { | 
 |         expr_ty expression; | 
 |         asdl_seq *seq1, *seq2; | 
 |  | 
 |         expression = ast_for_expr(c, CHILD(n, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         seq1 = ast_for_suite(c, CHILD(n, 3)); | 
 |         if (!seq1) | 
 |             return NULL; | 
 |         seq2 = ast_for_suite(c, CHILD(n, 6)); | 
 |         if (!seq2) | 
 |             return NULL; | 
 |  | 
 |         return While(expression, seq1, seq2, LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |  | 
 |     PyErr_Format(PyExc_SystemError, | 
 |                  "wrong number of tokens for 'while' statement: %d", | 
 |                  NCH(n)); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_for_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     asdl_seq *_target, *seq = NULL, *suite_seq; | 
 |     expr_ty expression; | 
 |     expr_ty target, first; | 
 |     const node *node_target; | 
 |     /* for_stmt: 'for' exprlist 'in' testlist ':' suite ['else' ':' suite] */ | 
 |     REQ(n, for_stmt); | 
 |  | 
 |     if (NCH(n) == 9) { | 
 |         seq = ast_for_suite(c, CHILD(n, 8)); | 
 |         if (!seq) | 
 |             return NULL; | 
 |     } | 
 |  | 
 |     node_target = CHILD(n, 1); | 
 |     _target = ast_for_exprlist(c, node_target, Store); | 
 |     if (!_target) | 
 |         return NULL; | 
 |     /* Check the # of children rather than the length of _target, since | 
 |        for x, in ... has 1 element in _target, but still requires a Tuple. */ | 
 |     first = (expr_ty)asdl_seq_GET(_target, 0); | 
 |     if (NCH(node_target) == 1) | 
 |         target = first; | 
 |     else | 
 |         target = Tuple(_target, Store, first->lineno, first->col_offset, c->c_arena); | 
 |  | 
 |     expression = ast_for_testlist(c, CHILD(n, 3)); | 
 |     if (!expression) | 
 |         return NULL; | 
 |     suite_seq = ast_for_suite(c, CHILD(n, 5)); | 
 |     if (!suite_seq) | 
 |         return NULL; | 
 |  | 
 |     return For(target, expression, suite_seq, seq, LINENO(n), n->n_col_offset, | 
 |                c->c_arena); | 
 | } | 
 |  | 
 | static excepthandler_ty | 
 | ast_for_except_clause(struct compiling *c, const node *exc, node *body) | 
 | { | 
 |     /* except_clause: 'except' [test ['as' test]] */ | 
 |     REQ(exc, except_clause); | 
 |     REQ(body, suite); | 
 |  | 
 |     if (NCH(exc) == 1) { | 
 |         asdl_seq *suite_seq = ast_for_suite(c, body); | 
 |         if (!suite_seq) | 
 |             return NULL; | 
 |  | 
 |         return ExceptHandler(NULL, NULL, suite_seq, LINENO(exc), | 
 |                              exc->n_col_offset, c->c_arena); | 
 |     } | 
 |     else if (NCH(exc) == 2) { | 
 |         expr_ty expression; | 
 |         asdl_seq *suite_seq; | 
 |  | 
 |         expression = ast_for_expr(c, CHILD(exc, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         suite_seq = ast_for_suite(c, body); | 
 |         if (!suite_seq) | 
 |             return NULL; | 
 |  | 
 |         return ExceptHandler(expression, NULL, suite_seq, LINENO(exc), | 
 |                              exc->n_col_offset, c->c_arena); | 
 |     } | 
 |     else if (NCH(exc) == 4) { | 
 |         asdl_seq *suite_seq; | 
 |         expr_ty expression; | 
 |         identifier e = NEW_IDENTIFIER(CHILD(exc, 3)); | 
 |         if (!e) | 
 |             return NULL; | 
 |         if (forbidden_name(e, CHILD(exc, 3), 0)) | 
 |             return NULL; | 
 |         expression = ast_for_expr(c, CHILD(exc, 1)); | 
 |         if (!expression) | 
 |             return NULL; | 
 |         suite_seq = ast_for_suite(c, body); | 
 |         if (!suite_seq) | 
 |             return NULL; | 
 |  | 
 |         return ExceptHandler(expression, e, suite_seq, LINENO(exc), | 
 |                              exc->n_col_offset, c->c_arena); | 
 |     } | 
 |  | 
 |     PyErr_Format(PyExc_SystemError, | 
 |                  "wrong number of children for 'except' clause: %d", | 
 |                  NCH(exc)); | 
 |     return NULL; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_try_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     const int nch = NCH(n); | 
 |     int n_except = (nch - 3)/3; | 
 |     asdl_seq *body, *orelse = NULL, *finally = NULL; | 
 |  | 
 |     REQ(n, try_stmt); | 
 |  | 
 |     body = ast_for_suite(c, CHILD(n, 2)); | 
 |     if (body == NULL) | 
 |         return NULL; | 
 |  | 
 |     if (TYPE(CHILD(n, nch - 3)) == NAME) { | 
 |         if (strcmp(STR(CHILD(n, nch - 3)), "finally") == 0) { | 
 |             if (nch >= 9 && TYPE(CHILD(n, nch - 6)) == NAME) { | 
 |                 /* we can assume it's an "else", | 
 |                    because nch >= 9 for try-else-finally and | 
 |                    it would otherwise have a type of except_clause */ | 
 |                 orelse = ast_for_suite(c, CHILD(n, nch - 4)); | 
 |                 if (orelse == NULL) | 
 |                     return NULL; | 
 |                 n_except--; | 
 |             } | 
 |  | 
 |             finally = ast_for_suite(c, CHILD(n, nch - 1)); | 
 |             if (finally == NULL) | 
 |                 return NULL; | 
 |             n_except--; | 
 |         } | 
 |         else { | 
 |             /* we can assume it's an "else", | 
 |                otherwise it would have a type of except_clause */ | 
 |             orelse = ast_for_suite(c, CHILD(n, nch - 1)); | 
 |             if (orelse == NULL) | 
 |                 return NULL; | 
 |             n_except--; | 
 |         } | 
 |     } | 
 |     else if (TYPE(CHILD(n, nch - 3)) != except_clause) { | 
 |         ast_error(n, "malformed 'try' statement"); | 
 |         return NULL; | 
 |     } | 
 |  | 
 |     if (n_except > 0) { | 
 |         int i; | 
 |         stmt_ty except_st; | 
 |         /* process except statements to create a try ... except */ | 
 |         asdl_seq *handlers = asdl_seq_new(n_except, c->c_arena); | 
 |         if (handlers == NULL) | 
 |             return NULL; | 
 |  | 
 |         for (i = 0; i < n_except; i++) { | 
 |             excepthandler_ty e = ast_for_except_clause(c, CHILD(n, 3 + i * 3), | 
 |                                                        CHILD(n, 5 + i * 3)); | 
 |             if (!e) | 
 |                 return NULL; | 
 |             asdl_seq_SET(handlers, i, e); | 
 |         } | 
 |  | 
 |         except_st = TryExcept(body, handlers, orelse, LINENO(n), | 
 |                               n->n_col_offset, c->c_arena); | 
 |         if (!finally) | 
 |             return except_st; | 
 |  | 
 |         /* if a 'finally' is present too, we nest the TryExcept within a | 
 |            TryFinally to emulate try ... except ... finally */ | 
 |         body = asdl_seq_new(1, c->c_arena); | 
 |         if (body == NULL) | 
 |             return NULL; | 
 |         asdl_seq_SET(body, 0, except_st); | 
 |     } | 
 |  | 
 |     /* must be a try ... finally (except clauses are in body, if any exist) */ | 
 |     assert(finally != NULL); | 
 |     return TryFinally(body, finally, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | /* with_item: test ['as' expr] */ | 
 | static stmt_ty | 
 | ast_for_with_item(struct compiling *c, const node *n, asdl_seq *content) | 
 | { | 
 |     expr_ty context_expr, optional_vars = NULL; | 
 |  | 
 |     REQ(n, with_item); | 
 |     context_expr = ast_for_expr(c, CHILD(n, 0)); | 
 |     if (NCH(n) == 3) { | 
 |         optional_vars = ast_for_expr(c, CHILD(n, 2)); | 
 |  | 
 |         if (!optional_vars) { | 
 |             return NULL; | 
 |         } | 
 |         if (!set_context(c, optional_vars, Store, n)) { | 
 |             return NULL; | 
 |         } | 
 |     } | 
 |  | 
 |     return With(context_expr, optional_vars, content, LINENO(n), | 
 |                 n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | /* with_stmt: 'with' with_item (',' with_item)* ':' suite */ | 
 | static stmt_ty | 
 | ast_for_with_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     int i; | 
 |     stmt_ty ret; | 
 |     asdl_seq *inner; | 
 |  | 
 |     REQ(n, with_stmt); | 
 |  | 
 |     /* process the with items inside-out */ | 
 |     i = NCH(n) - 1; | 
 |     /* the suite of the innermost with item is the suite of the with stmt */ | 
 |     inner = ast_for_suite(c, CHILD(n, i)); | 
 |     if (!inner) | 
 |         return NULL; | 
 |  | 
 |     for (;;) { | 
 |         i -= 2; | 
 |         ret = ast_for_with_item(c, CHILD(n, i), inner); | 
 |         if (!ret) | 
 |             return NULL; | 
 |         /* was this the last item? */ | 
 |         if (i == 1) | 
 |             break; | 
 |         /* if not, wrap the result so far in a new sequence */ | 
 |         inner = asdl_seq_new(1, c->c_arena); | 
 |         if (!inner) | 
 |             return NULL; | 
 |         asdl_seq_SET(inner, 0, ret); | 
 |     } | 
 |  | 
 |     return ret; | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_classdef(struct compiling *c, const node *n, asdl_seq *decorator_seq) | 
 | { | 
 |     /* classdef: 'class' NAME ['(' arglist ')'] ':' suite */ | 
 |     PyObject *classname; | 
 |     asdl_seq *s; | 
 |     expr_ty call; | 
 |  | 
 |     REQ(n, classdef); | 
 |  | 
 |     if (NCH(n) == 4) { /* class NAME ':' suite */ | 
 |         s = ast_for_suite(c, CHILD(n, 3)); | 
 |         if (!s) | 
 |             return NULL; | 
 |         classname = NEW_IDENTIFIER(CHILD(n, 1)); | 
 |         if (!classname) | 
 |             return NULL; | 
 |         if (forbidden_name(classname, CHILD(n, 3), 0)) | 
 |             return NULL; | 
 |         return ClassDef(classname, NULL, NULL, NULL, NULL, s, decorator_seq, | 
 |                         LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |  | 
 |     if (TYPE(CHILD(n, 3)) == RPAR) { /* class NAME '(' ')' ':' suite */ | 
 |         s = ast_for_suite(c, CHILD(n,5)); | 
 |         if (!s) | 
 |             return NULL; | 
 |         classname = NEW_IDENTIFIER(CHILD(n, 1)); | 
 |         if (!classname) | 
 |             return NULL; | 
 |         if (forbidden_name(classname, CHILD(n, 3), 0)) | 
 |             return NULL; | 
 |         return ClassDef(classname, NULL, NULL, NULL, NULL, s, decorator_seq, | 
 |                         LINENO(n), n->n_col_offset, c->c_arena); | 
 |     } | 
 |  | 
 |     /* class NAME '(' arglist ')' ':' suite */ | 
 |     /* build up a fake Call node so we can extract its pieces */ | 
 |     { | 
 |         PyObject *dummy_name; | 
 |         expr_ty dummy; | 
 |         dummy_name = NEW_IDENTIFIER(CHILD(n, 1)); | 
 |         if (!dummy_name) | 
 |             return NULL; | 
 |         dummy = Name(dummy_name, Load, LINENO(n), n->n_col_offset, c->c_arena); | 
 |         call = ast_for_call(c, CHILD(n, 3), dummy); | 
 |         if (!call) | 
 |             return NULL; | 
 |     } | 
 |     s = ast_for_suite(c, CHILD(n, 6)); | 
 |     if (!s) | 
 |         return NULL; | 
 |     classname = NEW_IDENTIFIER(CHILD(n, 1)); | 
 |     if (!classname) | 
 |         return NULL; | 
 |     if (forbidden_name(classname, CHILD(n, 1), 0)) | 
 |         return NULL; | 
 |  | 
 |     return ClassDef(classname, call->v.Call.args, call->v.Call.keywords, | 
 |                     call->v.Call.starargs, call->v.Call.kwargs, s, | 
 |                     decorator_seq, LINENO(n), n->n_col_offset, c->c_arena); | 
 | } | 
 |  | 
 | static stmt_ty | 
 | ast_for_stmt(struct compiling *c, const node *n) | 
 | { | 
 |     if (TYPE(n) == stmt) { | 
 |         assert(NCH(n) == 1); | 
 |         n = CHILD(n, 0); | 
 |     } | 
 |     if (TYPE(n) == simple_stmt) { | 
 |         assert(num_stmts(n) == 1); | 
 |         n = CHILD(n, 0); | 
 |     } | 
 |     if (TYPE(n) == small_stmt) { | 
 |         n = CHILD(n, 0); | 
 |         /* small_stmt: expr_stmt | del_stmt | pass_stmt | flow_stmt | 
 |                   | import_stmt | global_stmt | nonlocal_stmt | assert_stmt | 
 |         */ | 
 |         switch (TYPE(n)) { | 
 |             case expr_stmt: | 
 |                 return ast_for_expr_stmt(c, n); | 
 |             case del_stmt: | 
 |                 return ast_for_del_stmt(c, n); | 
 |             case pass_stmt: | 
 |                 return Pass(LINENO(n), n->n_col_offset, c->c_arena); | 
 |             case flow_stmt: | 
 |                 return ast_for_flow_stmt(c, n); | 
 |             case import_stmt: | 
 |                 return ast_for_import_stmt(c, n); | 
 |             case global_stmt: | 
 |                 return ast_for_global_stmt(c, n); | 
 |             case nonlocal_stmt: | 
 |                 return ast_for_nonlocal_stmt(c, n); | 
 |             case assert_stmt: | 
 |                 return ast_for_assert_stmt(c, n); | 
 |             default: | 
 |                 PyErr_Format(PyExc_SystemError, | 
 |                              "unhandled small_stmt: TYPE=%d NCH=%d\n", | 
 |                              TYPE(n), NCH(n)); | 
 |                 return NULL; | 
 |         } | 
 |     } | 
 |     else { | 
 |         /* compound_stmt: if_stmt | while_stmt | for_stmt | try_stmt | 
 |                         | funcdef | classdef | decorated | 
 |         */ | 
 |         node *ch = CHILD(n, 0); | 
 |         REQ(n, compound_stmt); | 
 |         switch (TYPE(ch)) { | 
 |             case if_stmt: | 
 |                 return ast_for_if_stmt(c, ch); | 
 |             case while_stmt: | 
 |                 return ast_for_while_stmt(c, ch); | 
 |             case for_stmt: | 
 |                 return ast_for_for_stmt(c, ch); | 
 |             case try_stmt: | 
 |                 return ast_for_try_stmt(c, ch); | 
 |             case with_stmt: | 
 |                 return ast_for_with_stmt(c, ch); | 
 |             case funcdef: | 
 |                 return ast_for_funcdef(c, ch, NULL); | 
 |             case classdef: | 
 |                 return ast_for_classdef(c, ch, NULL); | 
 |             case decorated: | 
 |                 return ast_for_decorated(c, ch); | 
 |             default: | 
 |                 PyErr_Format(PyExc_SystemError, | 
 |                              "unhandled small_stmt: TYPE=%d NCH=%d\n", | 
 |                              TYPE(n), NCH(n)); | 
 |                 return NULL; | 
 |         } | 
 |     } | 
 | } | 
 |  | 
 | static PyObject * | 
 | parsenumber(struct compiling *c, const char *s) | 
 | { | 
 |     const char *end; | 
 |     long x; | 
 |     double dx; | 
 |     Py_complex compl; | 
 |     int imflag; | 
 |  | 
 |     assert(s != NULL); | 
 |     errno = 0; | 
 |     end = s + strlen(s) - 1; | 
 |     imflag = *end == 'j' || *end == 'J'; | 
 |     if (s[0] == '0') { | 
 |         x = (long) PyOS_strtoul((char *)s, (char **)&end, 0); | 
 |         if (x < 0 && errno == 0) { | 
 |             return PyLong_FromString((char *)s, | 
 |                                      (char **)0, | 
 |                                      0); | 
 |         } | 
 |     } | 
 |     else | 
 |         x = PyOS_strtol((char *)s, (char **)&end, 0); | 
 |     if (*end == '\0') { | 
 |         if (errno != 0) | 
 |             return PyLong_FromString((char *)s, (char **)0, 0); | 
 |         return PyLong_FromLong(x); | 
 |     } | 
 |     /* XXX Huge floats may silently fail */ | 
 |     if (imflag) { | 
 |         compl.real = 0.; | 
 |         compl.imag = PyOS_string_to_double(s, (char **)&end, NULL); | 
 |         if (compl.imag == -1.0 && PyErr_Occurred()) | 
 |             return NULL; | 
 |         return PyComplex_FromCComplex(compl); | 
 |     } | 
 |     else | 
 |     { | 
 |         dx = PyOS_string_to_double(s, NULL, NULL); | 
 |         if (dx == -1.0 && PyErr_Occurred()) | 
 |             return NULL; | 
 |         return PyFloat_FromDouble(dx); | 
 |     } | 
 | } | 
 |  | 
 | static PyObject * | 
 | decode_utf8(struct compiling *c, const char **sPtr, const char *end, char* encoding) | 
 | { | 
 |     PyObject *u, *v; | 
 |     char *s, *t; | 
 |     t = s = (char *)*sPtr; | 
 |     /* while (s < end && *s != '\\') s++; */ /* inefficient for u".." */ | 
 |     while (s < end && (*s & 0x80)) s++; | 
 |     *sPtr = s; | 
 |     u = PyUnicode_DecodeUTF8(t, s - t, NULL); | 
 |     if (u == NULL) | 
 |         return NULL; | 
 |     v = PyUnicode_AsEncodedString(u, encoding, NULL); | 
 |     Py_DECREF(u); | 
 |     return v; | 
 | } | 
 |  | 
 | static PyObject * | 
 | decode_unicode(struct compiling *c, const char *s, size_t len, int rawmode, const char *encoding) | 
 | { | 
 |     PyObject *v, *u; | 
 |     char *buf; | 
 |     char *p; | 
 |     const char *end; | 
 |  | 
 |     if (encoding == NULL) { | 
 |         buf = (char *)s; | 
 |         u = NULL; | 
 |     } else { | 
 |         /* check for integer overflow */ | 
 |         if (len > PY_SIZE_MAX / 6) | 
 |             return NULL; | 
 |         /* "ä" (2 bytes) may become "\U000000E4" (10 bytes), or 1:5 | 
 |            "\ä" (3 bytes) may become "\u005c\U000000E4" (16 bytes), or ~1:6 */ | 
 |         u = PyBytes_FromStringAndSize((char *)NULL, len * 6); | 
 |         if (u == NULL) | 
 |             return NULL; | 
 |         p = buf = PyBytes_AsString(u); | 
 |         end = s + len; | 
 |         while (s < end) { | 
 |             if (*s == '\\') { | 
 |                 *p++ = *s++; | 
 |                 if (*s & 0x80) { | 
 |                     strcpy(p, "u005c"); | 
 |                     p += 5; | 
 |                 } | 
 |             } | 
 |             if (*s & 0x80) { /* XXX inefficient */ | 
 |                 PyObject *w; | 
 |                 char *r; | 
 |                 Py_ssize_t rn, i; | 
 |                 w = decode_utf8(c, &s, end, "utf-32-be"); | 
 |                 if (w == NULL) { | 
 |                     Py_DECREF(u); | 
 |                     return NULL; | 
 |                 } | 
 |                 r = PyBytes_AS_STRING(w); | 
 |                 rn = Py_SIZE(w); | 
 |                 assert(rn % 4 == 0); | 
 |                 for (i = 0; i < rn; i += 4) { | 
 |                     sprintf(p, "\\U%02x%02x%02x%02x", | 
 |                             r[i + 0] & 0xFF, | 
 |                             r[i + 1] & 0xFF, | 
 |                             r[i + 2] & 0xFF, | 
 |                             r[i + 3] & 0xFF); | 
 |                     p += 10; | 
 |                 } | 
 |                 /* Should be impossible to overflow */ | 
 |                 assert(p - buf <= Py_SIZE(u)); | 
 |                 Py_DECREF(w); | 
 |             } else { | 
 |                 *p++ = *s++; | 
 |             } | 
 |         } | 
 |         len = p - buf; | 
 |         s = buf; | 
 |     } | 
 |     if (rawmode) | 
 |         v = PyUnicode_DecodeRawUnicodeEscape(s, len, NULL); | 
 |     else | 
 |         v = PyUnicode_DecodeUnicodeEscape(s, len, NULL); | 
 |     Py_XDECREF(u); | 
 |     return v; | 
 | } | 
 |  | 
 | /* s is a Python string literal, including the bracketing quote characters, | 
 |  * and r &/or b prefixes (if any), and embedded escape sequences (if any). | 
 |  * parsestr parses it, and returns the decoded Python string object. | 
 |  */ | 
 | static PyObject * | 
 | parsestr(struct compiling *c, const node *n, int *bytesmode) | 
 | { | 
 |     size_t len; | 
 |     const char *s = STR(n); | 
 |     int quote = Py_CHARMASK(*s); | 
 |     int rawmode = 0; | 
 |     int need_encoding; | 
 |     if (isalpha(quote)) { | 
 |         if (quote == 'b' || quote == 'B') { | 
 |             quote = *++s; | 
 |             *bytesmode = 1; | 
 |         } | 
 |         if (quote == 'r' || quote == 'R') { | 
 |             quote = *++s; | 
 |             rawmode = 1; | 
 |         } | 
 |     } | 
 |     if (quote != '\'' && quote != '\"') { | 
 |         PyErr_BadInternalCall(); | 
 |         return NULL; | 
 |     } | 
 |     s++; | 
 |     len = strlen(s); | 
 |     if (len > INT_MAX) { | 
 |         PyErr_SetString(PyExc_OverflowError, | 
 |                         "string to parse is too long"); | 
 |         return NULL; | 
 |     } | 
 |     if (s[--len] != quote) { | 
 |         PyErr_BadInternalCall(); | 
 |         return NULL; | 
 |     } | 
 |     if (len >= 4 && s[0] == quote && s[1] == quote) { | 
 |         s += 2; | 
 |         len -= 2; | 
 |         if (s[--len] != quote || s[--len] != quote) { | 
 |             PyErr_BadInternalCall(); | 
 |             return NULL; | 
 |         } | 
 |     } | 
 |     if (!*bytesmode && !rawmode) { | 
 |         return decode_unicode(c, s, len, rawmode, c->c_encoding); | 
 |     } | 
 |     if (*bytesmode) { | 
 |         /* Disallow non-ascii characters (but not escapes) */ | 
 |         const char *c; | 
 |         for (c = s; *c; c++) { | 
 |             if (Py_CHARMASK(*c) >= 0x80) { | 
 |                 ast_error(n, "bytes can only contain ASCII " | 
 |                           "literal characters."); | 
 |                 return NULL; | 
 |             } | 
 |         } | 
 |     } | 
 |     need_encoding = (!*bytesmode && c->c_encoding != NULL && | 
 |                      strcmp(c->c_encoding, "utf-8") != 0); | 
 |     if (rawmode || strchr(s, '\\') == NULL) { | 
 |         if (need_encoding) { | 
 |             PyObject *v, *u = PyUnicode_DecodeUTF8(s, len, NULL); | 
 |             if (u == NULL || !*bytesmode) | 
 |                 return u; | 
 |             v = PyUnicode_AsEncodedString(u, c->c_encoding, NULL); | 
 |             Py_DECREF(u); | 
 |             return v; | 
 |         } else if (*bytesmode) { | 
 |             return PyBytes_FromStringAndSize(s, len); | 
 |         } else if (strcmp(c->c_encoding, "utf-8") == 0) { | 
 |             return PyUnicode_FromStringAndSize(s, len); | 
 |         } else { | 
 |             return PyUnicode_DecodeLatin1(s, len, NULL); | 
 |         } | 
 |     } | 
 |     return PyBytes_DecodeEscape(s, len, NULL, 1, | 
 |                                  need_encoding ? c->c_encoding : NULL); | 
 | } | 
 |  | 
 | /* Build a Python string object out of a STRING+ atom.  This takes care of | 
 |  * compile-time literal catenation, calling parsestr() on each piece, and | 
 |  * pasting the intermediate results together. | 
 |  */ | 
 | static PyObject * | 
 | parsestrplus(struct compiling *c, const node *n, int *bytesmode) | 
 | { | 
 |     PyObject *v; | 
 |     int i; | 
 |     REQ(CHILD(n, 0), STRING); | 
 |     v = parsestr(c, CHILD(n, 0), bytesmode); | 
 |     if (v != NULL) { | 
 |         /* String literal concatenation */ | 
 |         for (i = 1; i < NCH(n); i++) { | 
 |             PyObject *s; | 
 |             int subbm = 0; | 
 |             s = parsestr(c, CHILD(n, i), &subbm); | 
 |             if (s == NULL) | 
 |                 goto onError; | 
 |             if (*bytesmode != subbm) { | 
 |                 ast_error(n, "cannot mix bytes and nonbytes literals"); | 
 |                 goto onError; | 
 |             } | 
 |             if (PyBytes_Check(v) && PyBytes_Check(s)) { | 
 |                 PyBytes_ConcatAndDel(&v, s); | 
 |                 if (v == NULL) | 
 |                     goto onError; | 
 |             } | 
 |             else { | 
 |                 PyObject *temp = PyUnicode_Concat(v, s); | 
 |                 Py_DECREF(s); | 
 |                 Py_DECREF(v); | 
 |                 v = temp; | 
 |                 if (v == NULL) | 
 |                     goto onError; | 
 |             } | 
 |         } | 
 |     } | 
 |     return v; | 
 |  | 
 |   onError: | 
 |     Py_XDECREF(v); | 
 |     return NULL; | 
 | } |