| """Parse tree transformation module. |
| |
| Transforms Python source code into an abstract syntax tree (AST) |
| defined in the ast module. |
| |
| The simplest ways to invoke this module are via parse and parseFile. |
| parse(buf) -> AST |
| parseFile(path) -> AST |
| """ |
| |
| # Original version written by Greg Stein (gstein@lyra.org) |
| # and Bill Tutt (rassilon@lima.mudlib.org) |
| # February 1997. |
| # |
| # Modifications and improvements for Python 2.0 by Jeremy Hylton and |
| # Mark Hammond |
| |
| # Portions of this file are: |
| # Copyright (C) 1997-1998 Greg Stein. All Rights Reserved. |
| # |
| # This module is provided under a BSD-ish license. See |
| # http://www.opensource.org/licenses/bsd-license.html |
| # and replace OWNER, ORGANIZATION, and YEAR as appropriate. |
| |
| from ast import * |
| import parser |
| # Care must be taken to use only symbols and tokens defined in Python |
| # 1.5.2 for code branches executed in 1.5.2 |
| import symbol |
| import token |
| import sys |
| |
| error = 'walker.error' |
| |
| from consts import CO_VARARGS, CO_VARKEYWORDS |
| from consts import OP_ASSIGN, OP_DELETE, OP_APPLY |
| |
| def parseFile(path): |
| f = open(path) |
| # XXX The parser API tolerates files without a trailing newline, |
| # but not strings without a trailing newline. Always add an extra |
| # newline to the file contents, since we're going through the string |
| # version of the API. |
| src = f.read() + "\n" |
| f.close() |
| return parse(src) |
| |
| def parse(buf, mode="exec"): |
| if mode == "exec" or mode == "single": |
| return Transformer().parsesuite(buf) |
| elif mode == "eval": |
| return Transformer().parseexpr(buf) |
| else: |
| raise ValueError("compile() arg 3 must be" |
| " 'exec' or 'eval' or 'single'") |
| |
| def asList(nodes): |
| l = [] |
| for item in nodes: |
| if hasattr(item, "asList"): |
| l.append(item.asList()) |
| else: |
| if type(item) is type( (None, None) ): |
| l.append(tuple(asList(item))) |
| elif type(item) is type( [] ): |
| l.append(asList(item)) |
| else: |
| l.append(item) |
| return l |
| |
| def Node(*args): |
| kind = args[0] |
| if nodes.has_key(kind): |
| try: |
| return nodes[kind](*args[1:]) |
| except TypeError: |
| print nodes[kind], len(args), args |
| raise |
| else: |
| raise error, "Can't find appropriate Node type: %s" % str(args) |
| #return apply(ast.Node, args) |
| |
| class Transformer: |
| """Utility object for transforming Python parse trees. |
| |
| Exposes the following methods: |
| tree = transform(ast_tree) |
| tree = parsesuite(text) |
| tree = parseexpr(text) |
| tree = parsefile(fileob | filename) |
| """ |
| |
| def __init__(self): |
| self._dispatch = {} |
| for value, name in symbol.sym_name.items(): |
| if hasattr(self, name): |
| self._dispatch[value] = getattr(self, name) |
| self._dispatch[token.NEWLINE] = self.com_NEWLINE |
| self._atom_dispatch = {token.LPAR: self.atom_lpar, |
| token.LSQB: self.atom_lsqb, |
| token.LBRACE: self.atom_lbrace, |
| token.BACKQUOTE: self.atom_backquote, |
| token.NUMBER: self.atom_number, |
| token.STRING: self.atom_string, |
| token.NAME: self.atom_name, |
| } |
| self.encoding = None |
| |
| def transform(self, tree): |
| """Transform an AST into a modified parse tree.""" |
| if type(tree) != type(()) and type(tree) != type([]): |
| tree = parser.ast2tuple(tree, line_info=1) |
| return self.compile_node(tree) |
| |
| def parsesuite(self, text): |
| """Return a modified parse tree for the given suite text.""" |
| # Hack for handling non-native line endings on non-DOS like OSs. |
| # this can go now we have universal newlines? |
| text = text.replace('\x0d', '') |
| return self.transform(parser.suite(text)) |
| |
| def parseexpr(self, text): |
| """Return a modified parse tree for the given expression text.""" |
| return self.transform(parser.expr(text)) |
| |
| def parsefile(self, file): |
| """Return a modified parse tree for the contents of the given file.""" |
| if type(file) == type(''): |
| file = open(file) |
| return self.parsesuite(file.read()) |
| |
| # -------------------------------------------------------------- |
| # |
| # PRIVATE METHODS |
| # |
| |
| def compile_node(self, node): |
| ### emit a line-number node? |
| n = node[0] |
| |
| if n == symbol.encoding_decl: |
| self.encoding = node[2] |
| node = node[1] |
| n = node[0] |
| |
| if n == symbol.single_input: |
| return self.single_input(node[1:]) |
| if n == symbol.file_input: |
| return self.file_input(node[1:]) |
| if n == symbol.eval_input: |
| return self.eval_input(node[1:]) |
| if n == symbol.lambdef: |
| return self.lambdef(node[1:]) |
| if n == symbol.funcdef: |
| return self.funcdef(node[1:]) |
| if n == symbol.classdef: |
| return self.classdef(node[1:]) |
| |
| raise error, ('unexpected node type', n) |
| |
| def single_input(self, node): |
| ### do we want to do anything about being "interactive" ? |
| |
| # NEWLINE | simple_stmt | compound_stmt NEWLINE |
| n = node[0][0] |
| if n != token.NEWLINE: |
| return self.com_stmt(node[0]) |
| |
| return Pass() |
| |
| def file_input(self, nodelist): |
| doc = self.get_docstring(nodelist, symbol.file_input) |
| if doc is not None: |
| i = 1 |
| else: |
| i = 0 |
| stmts = [] |
| for node in nodelist[i:]: |
| if node[0] != token.ENDMARKER and node[0] != token.NEWLINE: |
| self.com_append_stmt(stmts, node) |
| return Module(doc, Stmt(stmts)) |
| |
| def eval_input(self, nodelist): |
| # from the built-in function input() |
| ### is this sufficient? |
| return Expression(self.com_node(nodelist[0])) |
| |
| def funcdef(self, nodelist): |
| # funcdef: 'def' NAME parameters ':' suite |
| # parameters: '(' [varargslist] ')' |
| |
| lineno = nodelist[1][2] |
| name = nodelist[1][1] |
| args = nodelist[2][2] |
| |
| if args[0] == symbol.varargslist: |
| names, defaults, flags = self.com_arglist(args[1:]) |
| else: |
| names = defaults = () |
| flags = 0 |
| doc = self.get_docstring(nodelist[4]) |
| |
| # code for function |
| code = self.com_node(nodelist[4]) |
| |
| if doc is not None: |
| assert isinstance(code, Stmt) |
| assert isinstance(code.nodes[0], Discard) |
| del code.nodes[0] |
| n = Function(name, names, defaults, flags, doc, code) |
| n.lineno = lineno |
| return n |
| |
| def lambdef(self, nodelist): |
| # lambdef: 'lambda' [varargslist] ':' test |
| if nodelist[2][0] == symbol.varargslist: |
| names, defaults, flags = self.com_arglist(nodelist[2][1:]) |
| else: |
| names = defaults = () |
| flags = 0 |
| |
| # code for lambda |
| code = self.com_node(nodelist[-1]) |
| |
| n = Lambda(names, defaults, flags, code) |
| n.lineno = nodelist[1][2] |
| return n |
| |
| def classdef(self, nodelist): |
| # classdef: 'class' NAME ['(' testlist ')'] ':' suite |
| |
| name = nodelist[1][1] |
| doc = self.get_docstring(nodelist[-1]) |
| if nodelist[2][0] == token.COLON: |
| bases = [] |
| else: |
| bases = self.com_bases(nodelist[3]) |
| |
| # code for class |
| code = self.com_node(nodelist[-1]) |
| |
| if doc is not None: |
| assert isinstance(code, Stmt) |
| assert isinstance(code.nodes[0], Discard) |
| del code.nodes[0] |
| |
| n = Class(name, bases, doc, code) |
| n.lineno = nodelist[1][2] |
| return n |
| |
| def stmt(self, nodelist): |
| return self.com_stmt(nodelist[0]) |
| |
| small_stmt = stmt |
| flow_stmt = stmt |
| compound_stmt = stmt |
| |
| def simple_stmt(self, nodelist): |
| # small_stmt (';' small_stmt)* [';'] NEWLINE |
| stmts = [] |
| for i in range(0, len(nodelist), 2): |
| self.com_append_stmt(stmts, nodelist[i]) |
| return Stmt(stmts) |
| |
| def parameters(self, nodelist): |
| raise error |
| |
| def varargslist(self, nodelist): |
| raise error |
| |
| def fpdef(self, nodelist): |
| raise error |
| |
| def fplist(self, nodelist): |
| raise error |
| |
| def dotted_name(self, nodelist): |
| raise error |
| |
| def comp_op(self, nodelist): |
| raise error |
| |
| def trailer(self, nodelist): |
| raise error |
| |
| def sliceop(self, nodelist): |
| raise error |
| |
| def argument(self, nodelist): |
| raise error |
| |
| # -------------------------------------------------------------- |
| # |
| # STATEMENT NODES (invoked by com_node()) |
| # |
| |
| def expr_stmt(self, nodelist): |
| # augassign testlist | testlist ('=' testlist)* |
| en = nodelist[-1] |
| exprNode = self.lookup_node(en)(en[1:]) |
| if len(nodelist) == 1: |
| n = Discard(exprNode) |
| n.lineno = exprNode.lineno |
| return n |
| if nodelist[1][0] == token.EQUAL: |
| nodesl = [] |
| for i in range(0, len(nodelist) - 2, 2): |
| nodesl.append(self.com_assign(nodelist[i], OP_ASSIGN)) |
| n = Assign(nodesl, exprNode) |
| n.lineno = nodelist[1][2] |
| else: |
| lval = self.com_augassign(nodelist[0]) |
| op = self.com_augassign_op(nodelist[1]) |
| n = AugAssign(lval, op[1], exprNode) |
| n.lineno = op[2] |
| return n |
| |
| def print_stmt(self, nodelist): |
| # print ([ test (',' test)* [','] ] | '>>' test [ (',' test)+ [','] ]) |
| items = [] |
| if len(nodelist) == 1: |
| start = 1 |
| dest = None |
| elif nodelist[1][0] == token.RIGHTSHIFT: |
| assert len(nodelist) == 3 \ |
| or nodelist[3][0] == token.COMMA |
| dest = self.com_node(nodelist[2]) |
| start = 4 |
| else: |
| dest = None |
| start = 1 |
| for i in range(start, len(nodelist), 2): |
| items.append(self.com_node(nodelist[i])) |
| if nodelist[-1][0] == token.COMMA: |
| n = Print(items, dest) |
| n.lineno = nodelist[0][2] |
| return n |
| n = Printnl(items, dest) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def del_stmt(self, nodelist): |
| return self.com_assign(nodelist[1], OP_DELETE) |
| |
| def pass_stmt(self, nodelist): |
| n = Pass() |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def break_stmt(self, nodelist): |
| n = Break() |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def continue_stmt(self, nodelist): |
| n = Continue() |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def return_stmt(self, nodelist): |
| # return: [testlist] |
| if len(nodelist) < 2: |
| n = Return(Const(None)) |
| n.lineno = nodelist[0][2] |
| return n |
| n = Return(self.com_node(nodelist[1])) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def yield_stmt(self, nodelist): |
| n = Yield(self.com_node(nodelist[1])) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def raise_stmt(self, nodelist): |
| # raise: [test [',' test [',' test]]] |
| if len(nodelist) > 5: |
| expr3 = self.com_node(nodelist[5]) |
| else: |
| expr3 = None |
| if len(nodelist) > 3: |
| expr2 = self.com_node(nodelist[3]) |
| else: |
| expr2 = None |
| if len(nodelist) > 1: |
| expr1 = self.com_node(nodelist[1]) |
| else: |
| expr1 = None |
| n = Raise(expr1, expr2, expr3) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def import_stmt(self, nodelist): |
| # import_stmt: 'import' dotted_as_name (',' dotted_as_name)* | |
| # from: 'from' dotted_name 'import' |
| # ('*' | import_as_name (',' import_as_name)*) |
| if nodelist[0][1] == 'from': |
| names = [] |
| if nodelist[3][0] == token.NAME: |
| for i in range(3, len(nodelist), 2): |
| names.append((nodelist[i][1], None)) |
| else: |
| for i in range(3, len(nodelist), 2): |
| names.append(self.com_import_as_name(nodelist[i])) |
| n = From(self.com_dotted_name(nodelist[1]), names) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| if nodelist[1][0] == symbol.dotted_name: |
| names = [(self.com_dotted_name(nodelist[1][1:]), None)] |
| else: |
| names = [] |
| for i in range(1, len(nodelist), 2): |
| names.append(self.com_dotted_as_name(nodelist[i])) |
| n = Import(names) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def global_stmt(self, nodelist): |
| # global: NAME (',' NAME)* |
| names = [] |
| for i in range(1, len(nodelist), 2): |
| names.append(nodelist[i][1]) |
| n = Global(names) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def exec_stmt(self, nodelist): |
| # exec_stmt: 'exec' expr ['in' expr [',' expr]] |
| expr1 = self.com_node(nodelist[1]) |
| if len(nodelist) >= 4: |
| expr2 = self.com_node(nodelist[3]) |
| if len(nodelist) >= 6: |
| expr3 = self.com_node(nodelist[5]) |
| else: |
| expr3 = None |
| else: |
| expr2 = expr3 = None |
| |
| n = Exec(expr1, expr2, expr3) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def assert_stmt(self, nodelist): |
| # 'assert': test, [',' test] |
| expr1 = self.com_node(nodelist[1]) |
| if (len(nodelist) == 4): |
| expr2 = self.com_node(nodelist[3]) |
| else: |
| expr2 = None |
| n = Assert(expr1, expr2) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def if_stmt(self, nodelist): |
| # if: test ':' suite ('elif' test ':' suite)* ['else' ':' suite] |
| tests = [] |
| for i in range(0, len(nodelist) - 3, 4): |
| testNode = self.com_node(nodelist[i + 1]) |
| suiteNode = self.com_node(nodelist[i + 3]) |
| tests.append((testNode, suiteNode)) |
| |
| if len(nodelist) % 4 == 3: |
| elseNode = self.com_node(nodelist[-1]) |
| ## elseNode.lineno = nodelist[-1][1][2] |
| else: |
| elseNode = None |
| n = If(tests, elseNode) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def while_stmt(self, nodelist): |
| # 'while' test ':' suite ['else' ':' suite] |
| |
| testNode = self.com_node(nodelist[1]) |
| bodyNode = self.com_node(nodelist[3]) |
| |
| if len(nodelist) > 4: |
| elseNode = self.com_node(nodelist[6]) |
| else: |
| elseNode = None |
| |
| n = While(testNode, bodyNode, elseNode) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def for_stmt(self, nodelist): |
| # 'for' exprlist 'in' exprlist ':' suite ['else' ':' suite] |
| |
| assignNode = self.com_assign(nodelist[1], OP_ASSIGN) |
| listNode = self.com_node(nodelist[3]) |
| bodyNode = self.com_node(nodelist[5]) |
| |
| if len(nodelist) > 8: |
| elseNode = self.com_node(nodelist[8]) |
| else: |
| elseNode = None |
| |
| n = For(assignNode, listNode, bodyNode, elseNode) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def try_stmt(self, nodelist): |
| # 'try' ':' suite (except_clause ':' suite)+ ['else' ':' suite] |
| # | 'try' ':' suite 'finally' ':' suite |
| if nodelist[3][0] != symbol.except_clause: |
| return self.com_try_finally(nodelist) |
| |
| return self.com_try_except(nodelist) |
| |
| def suite(self, nodelist): |
| # simple_stmt | NEWLINE INDENT NEWLINE* (stmt NEWLINE*)+ DEDENT |
| if len(nodelist) == 1: |
| return self.com_stmt(nodelist[0]) |
| |
| stmts = [] |
| for node in nodelist: |
| if node[0] == symbol.stmt: |
| self.com_append_stmt(stmts, node) |
| return Stmt(stmts) |
| |
| # -------------------------------------------------------------- |
| # |
| # EXPRESSION NODES (invoked by com_node()) |
| # |
| |
| def testlist(self, nodelist): |
| # testlist: expr (',' expr)* [','] |
| # testlist_safe: test [(',' test)+ [',']] |
| # exprlist: expr (',' expr)* [','] |
| return self.com_binary(Tuple, nodelist) |
| |
| testlist_safe = testlist # XXX |
| testlist1 = testlist |
| exprlist = testlist |
| |
| def testlist_gexp(self, nodelist): |
| if len(nodelist) == 2 and nodelist[1][0] == symbol.gen_for: |
| test = self.com_node(nodelist[0]) |
| return self.com_generator_expression(test, nodelist[1]) |
| return self.testlist(nodelist) |
| |
| def test(self, nodelist): |
| # and_test ('or' and_test)* | lambdef |
| if len(nodelist) == 1 and nodelist[0][0] == symbol.lambdef: |
| return self.lambdef(nodelist[0]) |
| return self.com_binary(Or, nodelist) |
| |
| def and_test(self, nodelist): |
| # not_test ('and' not_test)* |
| return self.com_binary(And, nodelist) |
| |
| def not_test(self, nodelist): |
| # 'not' not_test | comparison |
| result = self.com_node(nodelist[-1]) |
| if len(nodelist) == 2: |
| n = Not(result) |
| n.lineno = nodelist[0][2] |
| return n |
| return result |
| |
| def comparison(self, nodelist): |
| # comparison: expr (comp_op expr)* |
| node = self.com_node(nodelist[0]) |
| if len(nodelist) == 1: |
| return node |
| |
| results = [] |
| for i in range(2, len(nodelist), 2): |
| nl = nodelist[i-1] |
| |
| # comp_op: '<' | '>' | '=' | '>=' | '<=' | '<>' | '!=' | '==' |
| # | 'in' | 'not' 'in' | 'is' | 'is' 'not' |
| n = nl[1] |
| if n[0] == token.NAME: |
| type = n[1] |
| if len(nl) == 3: |
| if type == 'not': |
| type = 'not in' |
| else: |
| type = 'is not' |
| else: |
| type = _cmp_types[n[0]] |
| |
| lineno = nl[1][2] |
| results.append((type, self.com_node(nodelist[i]))) |
| |
| # we need a special "compare" node so that we can distinguish |
| # 3 < x < 5 from (3 < x) < 5 |
| # the two have very different semantics and results (note that the |
| # latter form is always true) |
| |
| n = Compare(node, results) |
| n.lineno = lineno |
| return n |
| |
| def expr(self, nodelist): |
| # xor_expr ('|' xor_expr)* |
| return self.com_binary(Bitor, nodelist) |
| |
| def xor_expr(self, nodelist): |
| # xor_expr ('^' xor_expr)* |
| return self.com_binary(Bitxor, nodelist) |
| |
| def and_expr(self, nodelist): |
| # xor_expr ('&' xor_expr)* |
| return self.com_binary(Bitand, nodelist) |
| |
| def shift_expr(self, nodelist): |
| # shift_expr ('<<'|'>>' shift_expr)* |
| node = self.com_node(nodelist[0]) |
| for i in range(2, len(nodelist), 2): |
| right = self.com_node(nodelist[i]) |
| if nodelist[i-1][0] == token.LEFTSHIFT: |
| node = LeftShift([node, right]) |
| node.lineno = nodelist[1][2] |
| elif nodelist[i-1][0] == token.RIGHTSHIFT: |
| node = RightShift([node, right]) |
| node.lineno = nodelist[1][2] |
| else: |
| raise ValueError, "unexpected token: %s" % nodelist[i-1][0] |
| return node |
| |
| def arith_expr(self, nodelist): |
| node = self.com_node(nodelist[0]) |
| for i in range(2, len(nodelist), 2): |
| right = self.com_node(nodelist[i]) |
| if nodelist[i-1][0] == token.PLUS: |
| node = Add([node, right]) |
| node.lineno = nodelist[1][2] |
| elif nodelist[i-1][0] == token.MINUS: |
| node = Sub([node, right]) |
| node.lineno = nodelist[1][2] |
| else: |
| raise ValueError, "unexpected token: %s" % nodelist[i-1][0] |
| return node |
| |
| def term(self, nodelist): |
| node = self.com_node(nodelist[0]) |
| for i in range(2, len(nodelist), 2): |
| right = self.com_node(nodelist[i]) |
| t = nodelist[i-1][0] |
| if t == token.STAR: |
| node = Mul([node, right]) |
| elif t == token.SLASH: |
| node = Div([node, right]) |
| elif t == token.PERCENT: |
| node = Mod([node, right]) |
| elif t == token.DOUBLESLASH: |
| node = FloorDiv([node, right]) |
| else: |
| raise ValueError, "unexpected token: %s" % t |
| node.lineno = nodelist[1][2] |
| return node |
| |
| def factor(self, nodelist): |
| elt = nodelist[0] |
| t = elt[0] |
| node = self.com_node(nodelist[-1]) |
| # need to handle (unary op)constant here... |
| if t == token.PLUS: |
| node = UnaryAdd(node) |
| node.lineno = elt[2] |
| elif t == token.MINUS: |
| node = UnarySub(node) |
| node.lineno = elt[2] |
| elif t == token.TILDE: |
| node = Invert(node) |
| node.lineno = elt[2] |
| return node |
| |
| def power(self, nodelist): |
| # power: atom trailer* ('**' factor)* |
| node = self.com_node(nodelist[0]) |
| for i in range(1, len(nodelist)): |
| elt = nodelist[i] |
| if elt[0] == token.DOUBLESTAR: |
| n = Power([node, self.com_node(nodelist[i+1])]) |
| n.lineno = elt[2] |
| return n |
| |
| node = self.com_apply_trailer(node, elt) |
| |
| return node |
| |
| def atom(self, nodelist): |
| n = self._atom_dispatch[nodelist[0][0]](nodelist) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def atom_lpar(self, nodelist): |
| if nodelist[1][0] == token.RPAR: |
| n = Tuple(()) |
| n.lineno = nodelist[0][2] |
| return n |
| return self.com_node(nodelist[1]) |
| |
| def atom_lsqb(self, nodelist): |
| if nodelist[1][0] == token.RSQB: |
| n = List(()) |
| n.lineno = nodelist[0][2] |
| return n |
| return self.com_list_constructor(nodelist[1]) |
| |
| def atom_lbrace(self, nodelist): |
| if nodelist[1][0] == token.RBRACE: |
| return Dict(()) |
| return self.com_dictmaker(nodelist[1]) |
| |
| def atom_backquote(self, nodelist): |
| n = Backquote(self.com_node(nodelist[1])) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def atom_number(self, nodelist): |
| ### need to verify this matches compile.c |
| k = eval(nodelist[0][1]) |
| n = Const(k) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def decode_literal(self, lit): |
| if self.encoding: |
| # this is particularly fragile & a bit of a |
| # hack... changes in compile.c:parsestr and |
| # tokenizer.c must be reflected here. |
| if self.encoding not in ['utf-8', 'iso-8859-1']: |
| lit = unicode(lit, 'utf-8').encode(self.encoding) |
| return eval("# coding: %s\n%s" % (self.encoding, lit)) |
| else: |
| return eval(lit) |
| |
| def atom_string(self, nodelist): |
| k = '' |
| for node in nodelist: |
| k += self.decode_literal(node[1]) |
| n = Const(k) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def atom_name(self, nodelist): |
| ### any processing to do? |
| n = Name(nodelist[0][1]) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| # -------------------------------------------------------------- |
| # |
| # INTERNAL PARSING UTILITIES |
| # |
| |
| # The use of com_node() introduces a lot of extra stack frames, |
| # enough to cause a stack overflow compiling test.test_parser with |
| # the standard interpreter recursionlimit. The com_node() is a |
| # convenience function that hides the dispatch details, but comes |
| # at a very high cost. It is more efficient to dispatch directly |
| # in the callers. In these cases, use lookup_node() and call the |
| # dispatched node directly. |
| |
| def lookup_node(self, node): |
| return self._dispatch[node[0]] |
| |
| def com_node(self, node): |
| # Note: compile.c has handling in com_node for del_stmt, pass_stmt, |
| # break_stmt, stmt, small_stmt, flow_stmt, simple_stmt, |
| # and compound_stmt. |
| # We'll just dispatch them. |
| return self._dispatch[node[0]](node[1:]) |
| |
| def com_NEWLINE(self, *args): |
| # A ';' at the end of a line can make a NEWLINE token appear |
| # here, Render it harmless. (genc discards ('discard', |
| # ('const', xxxx)) Nodes) |
| return Discard(Const(None)) |
| |
| def com_arglist(self, nodelist): |
| # varargslist: |
| # (fpdef ['=' test] ',')* ('*' NAME [',' '**' NAME] | '**' NAME) |
| # | fpdef ['=' test] (',' fpdef ['=' test])* [','] |
| # fpdef: NAME | '(' fplist ')' |
| # fplist: fpdef (',' fpdef)* [','] |
| names = [] |
| defaults = [] |
| flags = 0 |
| |
| i = 0 |
| while i < len(nodelist): |
| node = nodelist[i] |
| if node[0] == token.STAR or node[0] == token.DOUBLESTAR: |
| if node[0] == token.STAR: |
| node = nodelist[i+1] |
| if node[0] == token.NAME: |
| names.append(node[1]) |
| flags = flags | CO_VARARGS |
| i = i + 3 |
| |
| if i < len(nodelist): |
| # should be DOUBLESTAR |
| t = nodelist[i][0] |
| if t == token.DOUBLESTAR: |
| node = nodelist[i+1] |
| else: |
| raise ValueError, "unexpected token: %s" % t |
| names.append(node[1]) |
| flags = flags | CO_VARKEYWORDS |
| |
| break |
| |
| # fpdef: NAME | '(' fplist ')' |
| names.append(self.com_fpdef(node)) |
| |
| i = i + 1 |
| if i >= len(nodelist): |
| break |
| |
| if nodelist[i][0] == token.EQUAL: |
| defaults.append(self.com_node(nodelist[i + 1])) |
| i = i + 2 |
| elif len(defaults): |
| # Treat "(a=1, b)" as "(a=1, b=None)" |
| defaults.append(Const(None)) |
| |
| i = i + 1 |
| |
| return names, defaults, flags |
| |
| def com_fpdef(self, node): |
| # fpdef: NAME | '(' fplist ')' |
| if node[1][0] == token.LPAR: |
| return self.com_fplist(node[2]) |
| return node[1][1] |
| |
| def com_fplist(self, node): |
| # fplist: fpdef (',' fpdef)* [','] |
| if len(node) == 2: |
| return self.com_fpdef(node[1]) |
| list = [] |
| for i in range(1, len(node), 2): |
| list.append(self.com_fpdef(node[i])) |
| return tuple(list) |
| |
| def com_dotted_name(self, node): |
| # String together the dotted names and return the string |
| name = "" |
| for n in node: |
| if type(n) == type(()) and n[0] == 1: |
| name = name + n[1] + '.' |
| return name[:-1] |
| |
| def com_dotted_as_name(self, node): |
| dot = self.com_dotted_name(node[1]) |
| if len(node) <= 2: |
| return dot, None |
| if node[0] == symbol.dotted_name: |
| pass |
| else: |
| assert node[2][1] == 'as' |
| assert node[3][0] == token.NAME |
| return dot, node[3][1] |
| |
| def com_import_as_name(self, node): |
| if node[0] == token.STAR: |
| return '*', None |
| assert node[0] == symbol.import_as_name |
| node = node[1:] |
| if len(node) == 1: |
| assert node[0][0] == token.NAME |
| return node[0][1], None |
| |
| assert node[1][1] == 'as', node |
| assert node[2][0] == token.NAME |
| return node[0][1], node[2][1] |
| |
| def com_bases(self, node): |
| bases = [] |
| for i in range(1, len(node), 2): |
| bases.append(self.com_node(node[i])) |
| return bases |
| |
| def com_try_finally(self, nodelist): |
| # try_fin_stmt: "try" ":" suite "finally" ":" suite |
| n = TryFinally(self.com_node(nodelist[2]), |
| self.com_node(nodelist[5])) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def com_try_except(self, nodelist): |
| # try_except: 'try' ':' suite (except_clause ':' suite)* ['else' suite] |
| #tryexcept: [TryNode, [except_clauses], elseNode)] |
| stmt = self.com_node(nodelist[2]) |
| clauses = [] |
| elseNode = None |
| for i in range(3, len(nodelist), 3): |
| node = nodelist[i] |
| if node[0] == symbol.except_clause: |
| # except_clause: 'except' [expr [',' expr]] */ |
| if len(node) > 2: |
| expr1 = self.com_node(node[2]) |
| if len(node) > 4: |
| expr2 = self.com_assign(node[4], OP_ASSIGN) |
| else: |
| expr2 = None |
| else: |
| expr1 = expr2 = None |
| clauses.append((expr1, expr2, self.com_node(nodelist[i+2]))) |
| |
| if node[0] == token.NAME: |
| elseNode = self.com_node(nodelist[i+2]) |
| n = TryExcept(self.com_node(nodelist[2]), clauses, elseNode) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def com_augassign_op(self, node): |
| assert node[0] == symbol.augassign |
| return node[1] |
| |
| def com_augassign(self, node): |
| """Return node suitable for lvalue of augmented assignment |
| |
| Names, slices, and attributes are the only allowable nodes. |
| """ |
| l = self.com_node(node) |
| if l.__class__ in (Name, Slice, Subscript, Getattr): |
| return l |
| raise SyntaxError, "can't assign to %s" % l.__class__.__name__ |
| |
| def com_assign(self, node, assigning): |
| # return a node suitable for use as an "lvalue" |
| # loop to avoid trivial recursion |
| while 1: |
| t = node[0] |
| if t == symbol.exprlist or t == symbol.testlist: |
| if len(node) > 2: |
| return self.com_assign_tuple(node, assigning) |
| node = node[1] |
| elif t in _assign_types: |
| if len(node) > 2: |
| raise SyntaxError, "can't assign to operator" |
| node = node[1] |
| elif t == symbol.power: |
| if node[1][0] != symbol.atom: |
| raise SyntaxError, "can't assign to operator" |
| if len(node) > 2: |
| primary = self.com_node(node[1]) |
| for i in range(2, len(node)-1): |
| ch = node[i] |
| if ch[0] == token.DOUBLESTAR: |
| raise SyntaxError, "can't assign to operator" |
| primary = self.com_apply_trailer(primary, ch) |
| return self.com_assign_trailer(primary, node[-1], |
| assigning) |
| node = node[1] |
| elif t == symbol.atom: |
| t = node[1][0] |
| if t == token.LPAR: |
| node = node[2] |
| if node[0] == token.RPAR: |
| raise SyntaxError, "can't assign to ()" |
| elif t == token.LSQB: |
| node = node[2] |
| if node[0] == token.RSQB: |
| raise SyntaxError, "can't assign to []" |
| return self.com_assign_list(node, assigning) |
| elif t == token.NAME: |
| return self.com_assign_name(node[1], assigning) |
| else: |
| raise SyntaxError, "can't assign to literal" |
| else: |
| raise SyntaxError, "bad assignment" |
| |
| def com_assign_tuple(self, node, assigning): |
| assigns = [] |
| for i in range(1, len(node), 2): |
| assigns.append(self.com_assign(node[i], assigning)) |
| return AssTuple(assigns) |
| |
| def com_assign_list(self, node, assigning): |
| assigns = [] |
| for i in range(1, len(node), 2): |
| if i + 1 < len(node): |
| if node[i + 1][0] == symbol.list_for: |
| raise SyntaxError, "can't assign to list comprehension" |
| assert node[i + 1][0] == token.COMMA, node[i + 1] |
| assigns.append(self.com_assign(node[i], assigning)) |
| return AssList(assigns) |
| |
| def com_assign_name(self, node, assigning): |
| n = AssName(node[1], assigning) |
| n.lineno = node[2] |
| return n |
| |
| def com_assign_trailer(self, primary, node, assigning): |
| t = node[1][0] |
| if t == token.DOT: |
| return self.com_assign_attr(primary, node[2], assigning) |
| if t == token.LSQB: |
| return self.com_subscriptlist(primary, node[2], assigning) |
| if t == token.LPAR: |
| raise SyntaxError, "can't assign to function call" |
| raise SyntaxError, "unknown trailer type: %s" % t |
| |
| def com_assign_attr(self, primary, node, assigning): |
| return AssAttr(primary, node[1], assigning) |
| |
| def com_binary(self, constructor, nodelist): |
| "Compile 'NODE (OP NODE)*' into (type, [ node1, ..., nodeN ])." |
| l = len(nodelist) |
| if l == 1: |
| n = nodelist[0] |
| return self.lookup_node(n)(n[1:]) |
| items = [] |
| for i in range(0, l, 2): |
| n = nodelist[i] |
| items.append(self.lookup_node(n)(n[1:])) |
| return constructor(items) |
| |
| def com_stmt(self, node): |
| result = self.lookup_node(node)(node[1:]) |
| assert result is not None |
| if isinstance(result, Stmt): |
| return result |
| return Stmt([result]) |
| |
| def com_append_stmt(self, stmts, node): |
| result = self.com_node(node) |
| assert result is not None |
| if isinstance(result, Stmt): |
| stmts.extend(result.nodes) |
| else: |
| stmts.append(result) |
| |
| if hasattr(symbol, 'list_for'): |
| def com_list_constructor(self, nodelist): |
| # listmaker: test ( list_for | (',' test)* [','] ) |
| values = [] |
| for i in range(1, len(nodelist)): |
| if nodelist[i][0] == symbol.list_for: |
| assert len(nodelist[i:]) == 1 |
| return self.com_list_comprehension(values[0], |
| nodelist[i]) |
| elif nodelist[i][0] == token.COMMA: |
| continue |
| values.append(self.com_node(nodelist[i])) |
| return List(values) |
| |
| def com_list_comprehension(self, expr, node): |
| # list_iter: list_for | list_if |
| # list_for: 'for' exprlist 'in' testlist [list_iter] |
| # list_if: 'if' test [list_iter] |
| |
| # XXX should raise SyntaxError for assignment |
| |
| lineno = node[1][2] |
| fors = [] |
| while node: |
| t = node[1][1] |
| if t == 'for': |
| assignNode = self.com_assign(node[2], OP_ASSIGN) |
| listNode = self.com_node(node[4]) |
| newfor = ListCompFor(assignNode, listNode, []) |
| newfor.lineno = node[1][2] |
| fors.append(newfor) |
| if len(node) == 5: |
| node = None |
| else: |
| node = self.com_list_iter(node[5]) |
| elif t == 'if': |
| test = self.com_node(node[2]) |
| newif = ListCompIf(test) |
| newif.lineno = node[1][2] |
| newfor.ifs.append(newif) |
| if len(node) == 3: |
| node = None |
| else: |
| node = self.com_list_iter(node[3]) |
| else: |
| raise SyntaxError, \ |
| ("unexpected list comprehension element: %s %d" |
| % (node, lineno)) |
| n = ListComp(expr, fors) |
| n.lineno = lineno |
| return n |
| |
| def com_list_iter(self, node): |
| assert node[0] == symbol.list_iter |
| return node[1] |
| else: |
| def com_list_constructor(self, nodelist): |
| values = [] |
| for i in range(1, len(nodelist), 2): |
| values.append(self.com_node(nodelist[i])) |
| return List(values) |
| |
| if hasattr(symbol, 'gen_for'): |
| def com_generator_expression(self, expr, node): |
| # gen_iter: gen_for | gen_if |
| # gen_for: 'for' exprlist 'in' test [gen_iter] |
| # gen_if: 'if' test [gen_iter] |
| |
| lineno = node[1][2] |
| fors = [] |
| while node: |
| t = node[1][1] |
| if t == 'for': |
| assignNode = self.com_assign(node[2], OP_ASSIGN) |
| genNode = self.com_node(node[4]) |
| newfor = GenExprFor(assignNode, genNode, []) |
| newfor.lineno = node[1][2] |
| fors.append(newfor) |
| if (len(node)) == 5: |
| node = None |
| else: |
| node = self.com_gen_iter(node[5]) |
| elif t == 'if': |
| test = self.com_node(node[2]) |
| newif = GenExprIf(test) |
| newif.lineno = node[1][2] |
| newfor.ifs.append(newif) |
| if len(node) == 3: |
| node = None |
| else: |
| node = self.com_gen_iter(node[3]) |
| else: |
| raise SyntaxError, \ |
| ("unexpected generator expression element: %s %d" |
| % (node, lineno)) |
| fors[0].is_outmost = True |
| n = GenExpr(GenExprInner(expr, fors)) |
| n.lineno = lineno |
| return n |
| |
| def com_gen_iter(self, node): |
| assert node[0] == symbol.gen_iter |
| return node[1] |
| |
| def com_dictmaker(self, nodelist): |
| # dictmaker: test ':' test (',' test ':' value)* [','] |
| items = [] |
| for i in range(1, len(nodelist), 4): |
| items.append((self.com_node(nodelist[i]), |
| self.com_node(nodelist[i+2]))) |
| return Dict(items) |
| |
| def com_apply_trailer(self, primaryNode, nodelist): |
| t = nodelist[1][0] |
| if t == token.LPAR: |
| return self.com_call_function(primaryNode, nodelist[2]) |
| if t == token.DOT: |
| return self.com_select_member(primaryNode, nodelist[2]) |
| if t == token.LSQB: |
| return self.com_subscriptlist(primaryNode, nodelist[2], OP_APPLY) |
| |
| raise SyntaxError, 'unknown node type: %s' % t |
| |
| def com_select_member(self, primaryNode, nodelist): |
| if nodelist[0] != token.NAME: |
| raise SyntaxError, "member must be a name" |
| n = Getattr(primaryNode, nodelist[1]) |
| n.lineno = nodelist[2] |
| return n |
| |
| def com_call_function(self, primaryNode, nodelist): |
| if nodelist[0] == token.RPAR: |
| return CallFunc(primaryNode, []) |
| args = [] |
| kw = 0 |
| len_nodelist = len(nodelist) |
| for i in range(1, len_nodelist, 2): |
| node = nodelist[i] |
| if node[0] == token.STAR or node[0] == token.DOUBLESTAR: |
| break |
| kw, result = self.com_argument(node, kw) |
| if len_nodelist != 2 and isinstance(result, GenExpr): |
| raise SyntaxError, 'generator expression needs parenthesis' |
| args.append(result) |
| else: |
| # No broken by star arg, so skip the last one we processed. |
| i = i + 1 |
| if i < len_nodelist and nodelist[i][0] == token.COMMA: |
| # need to accept an application that looks like "f(a, b,)" |
| i = i + 1 |
| star_node = dstar_node = None |
| while i < len_nodelist: |
| tok = nodelist[i] |
| ch = nodelist[i+1] |
| i = i + 3 |
| if tok[0]==token.STAR: |
| if star_node is not None: |
| raise SyntaxError, 'already have the varargs indentifier' |
| star_node = self.com_node(ch) |
| elif tok[0]==token.DOUBLESTAR: |
| if dstar_node is not None: |
| raise SyntaxError, 'already have the kwargs indentifier' |
| dstar_node = self.com_node(ch) |
| else: |
| raise SyntaxError, 'unknown node type: %s' % tok |
| |
| return CallFunc(primaryNode, args, star_node, dstar_node) |
| |
| def com_argument(self, nodelist, kw): |
| if len(nodelist) == 3 and nodelist[2][0] == symbol.gen_for: |
| test = self.com_node(nodelist[1]) |
| return 0, self.com_generator_expression(test, nodelist[2]) |
| if len(nodelist) == 2: |
| if kw: |
| raise SyntaxError, "non-keyword arg after keyword arg" |
| return 0, self.com_node(nodelist[1]) |
| result = self.com_node(nodelist[3]) |
| n = nodelist[1] |
| while len(n) == 2 and n[0] != token.NAME: |
| n = n[1] |
| if n[0] != token.NAME: |
| raise SyntaxError, "keyword can't be an expression (%s)"%n[0] |
| node = Keyword(n[1], result) |
| node.lineno = n[2] |
| return 1, node |
| |
| def com_subscriptlist(self, primary, nodelist, assigning): |
| # slicing: simple_slicing | extended_slicing |
| # simple_slicing: primary "[" short_slice "]" |
| # extended_slicing: primary "[" slice_list "]" |
| # slice_list: slice_item ("," slice_item)* [","] |
| |
| # backwards compat slice for '[i:j]' |
| if len(nodelist) == 2: |
| sub = nodelist[1] |
| if (sub[1][0] == token.COLON or \ |
| (len(sub) > 2 and sub[2][0] == token.COLON)) and \ |
| sub[-1][0] != symbol.sliceop: |
| return self.com_slice(primary, sub, assigning) |
| |
| subscripts = [] |
| for i in range(1, len(nodelist), 2): |
| subscripts.append(self.com_subscript(nodelist[i])) |
| |
| return Subscript(primary, assigning, subscripts) |
| |
| def com_subscript(self, node): |
| # slice_item: expression | proper_slice | ellipsis |
| ch = node[1] |
| t = ch[0] |
| if t == token.DOT and node[2][0] == token.DOT: |
| return Ellipsis() |
| if t == token.COLON or len(node) > 2: |
| return self.com_sliceobj(node) |
| return self.com_node(ch) |
| |
| def com_sliceobj(self, node): |
| # proper_slice: short_slice | long_slice |
| # short_slice: [lower_bound] ":" [upper_bound] |
| # long_slice: short_slice ":" [stride] |
| # lower_bound: expression |
| # upper_bound: expression |
| # stride: expression |
| # |
| # Note: a stride may be further slicing... |
| |
| items = [] |
| |
| if node[1][0] == token.COLON: |
| items.append(Const(None)) |
| i = 2 |
| else: |
| items.append(self.com_node(node[1])) |
| # i == 2 is a COLON |
| i = 3 |
| |
| if i < len(node) and node[i][0] == symbol.test: |
| items.append(self.com_node(node[i])) |
| i = i + 1 |
| else: |
| items.append(Const(None)) |
| |
| # a short_slice has been built. look for long_slice now by looking |
| # for strides... |
| for j in range(i, len(node)): |
| ch = node[j] |
| if len(ch) == 2: |
| items.append(Const(None)) |
| else: |
| items.append(self.com_node(ch[2])) |
| |
| return Sliceobj(items) |
| |
| def com_slice(self, primary, node, assigning): |
| # short_slice: [lower_bound] ":" [upper_bound] |
| lower = upper = None |
| if len(node) == 3: |
| if node[1][0] == token.COLON: |
| upper = self.com_node(node[2]) |
| else: |
| lower = self.com_node(node[1]) |
| elif len(node) == 4: |
| lower = self.com_node(node[1]) |
| upper = self.com_node(node[3]) |
| return Slice(primary, assigning, lower, upper) |
| |
| def get_docstring(self, node, n=None): |
| if n is None: |
| n = node[0] |
| node = node[1:] |
| if n == symbol.suite: |
| if len(node) == 1: |
| return self.get_docstring(node[0]) |
| for sub in node: |
| if sub[0] == symbol.stmt: |
| return self.get_docstring(sub) |
| return None |
| if n == symbol.file_input: |
| for sub in node: |
| if sub[0] == symbol.stmt: |
| return self.get_docstring(sub) |
| return None |
| if n == symbol.atom: |
| if node[0][0] == token.STRING: |
| s = '' |
| for t in node: |
| s = s + eval(t[1]) |
| return s |
| return None |
| if n == symbol.stmt or n == symbol.simple_stmt \ |
| or n == symbol.small_stmt: |
| return self.get_docstring(node[0]) |
| if n in _doc_nodes and len(node) == 1: |
| return self.get_docstring(node[0]) |
| return None |
| |
| |
| _doc_nodes = [ |
| symbol.expr_stmt, |
| symbol.testlist, |
| symbol.testlist_safe, |
| symbol.test, |
| symbol.and_test, |
| symbol.not_test, |
| symbol.comparison, |
| symbol.expr, |
| symbol.xor_expr, |
| symbol.and_expr, |
| symbol.shift_expr, |
| symbol.arith_expr, |
| symbol.term, |
| symbol.factor, |
| symbol.power, |
| ] |
| |
| # comp_op: '<' | '>' | '=' | '>=' | '<=' | '<>' | '!=' | '==' |
| # | 'in' | 'not' 'in' | 'is' | 'is' 'not' |
| _cmp_types = { |
| token.LESS : '<', |
| token.GREATER : '>', |
| token.EQEQUAL : '==', |
| token.EQUAL : '==', |
| token.LESSEQUAL : '<=', |
| token.GREATEREQUAL : '>=', |
| token.NOTEQUAL : '!=', |
| } |
| |
| _legal_node_types = [ |
| symbol.funcdef, |
| symbol.classdef, |
| symbol.stmt, |
| symbol.small_stmt, |
| symbol.flow_stmt, |
| symbol.simple_stmt, |
| symbol.compound_stmt, |
| symbol.expr_stmt, |
| symbol.print_stmt, |
| symbol.del_stmt, |
| symbol.pass_stmt, |
| symbol.break_stmt, |
| symbol.continue_stmt, |
| symbol.return_stmt, |
| symbol.raise_stmt, |
| symbol.import_stmt, |
| symbol.global_stmt, |
| symbol.exec_stmt, |
| symbol.assert_stmt, |
| symbol.if_stmt, |
| symbol.while_stmt, |
| symbol.for_stmt, |
| symbol.try_stmt, |
| symbol.suite, |
| symbol.testlist, |
| symbol.testlist_safe, |
| symbol.test, |
| symbol.and_test, |
| symbol.not_test, |
| symbol.comparison, |
| symbol.exprlist, |
| symbol.expr, |
| symbol.xor_expr, |
| symbol.and_expr, |
| symbol.shift_expr, |
| symbol.arith_expr, |
| symbol.term, |
| symbol.factor, |
| symbol.power, |
| symbol.atom, |
| ] |
| |
| if hasattr(symbol, 'yield_stmt'): |
| _legal_node_types.append(symbol.yield_stmt) |
| |
| _assign_types = [ |
| symbol.test, |
| symbol.and_test, |
| symbol.not_test, |
| symbol.comparison, |
| symbol.expr, |
| symbol.xor_expr, |
| symbol.and_expr, |
| symbol.shift_expr, |
| symbol.arith_expr, |
| symbol.term, |
| symbol.factor, |
| ] |
| |
| import types |
| _names = {} |
| for k, v in symbol.sym_name.items(): |
| _names[k] = v |
| for k, v in token.tok_name.items(): |
| _names[k] = v |
| |
| def debug_tree(tree): |
| l = [] |
| for elt in tree: |
| if type(elt) == types.IntType: |
| l.append(_names.get(elt, elt)) |
| elif type(elt) == types.StringType: |
| l.append(elt) |
| else: |
| l.append(debug_tree(elt)) |
| return l |