| # Copyright 1997-1998 Greg Stein and Bill Tutt |
| # |
| # transformer.py -- transforms Python parse trees |
| # |
| # Takes an input parse tree and transforms it into a higher-level parse |
| # tree that is a bit more amenable to code generation. Essentially, it |
| # simply introduces some additional semantics. |
| # |
| # Written by Greg Stein (gstein@lyra.org) |
| # and Bill Tutt (rassilon@lima.mudlib.org) |
| # February 1997. |
| # |
| # Support for Node subclasses written by |
| # Jeremy Hylton (jeremy@cnri.reston.va.us) |
| # |
| # The output tree has the following nodes: |
| # |
| # Source Python line #'s appear at the end of each of all of these nodes |
| # If a line # doesn't apply, there will be a None instead. |
| # |
| # module: doc, node |
| # stmt: [ node1, ..., nodeN ] |
| # function: name, argnames, defaults, flags, doc, codeNode |
| # lambda: argnames, defaults, flags, codeNode |
| # classdef: name, bases, doc, codeNode |
| # pass: |
| # break: |
| # continue: |
| # for: assignNode, listNode, bodyNode, elseNode |
| # while: testNode, bodyNode, elseNode |
| # if: [ (testNode, suiteNode), ... ], elseNode |
| # exec: expr1Node, expr2Node, expr3Node |
| # from: modname, [ name1, ..., nameN ] |
| # import: [ name1, ..., nameN ] |
| # raise: expr1Node, expr2Node, expr3Node |
| # tryfinally: trySuiteNode, finSuiteNode |
| # tryexcept: trySuiteNode, [ (exprNode, assgnNode, suiteNode), ... ], elseNode |
| # return: valueNode |
| # const: value |
| # print: [ node1, ..., nodeN ] |
| # printnl: [ node1, ..., nodeN ] |
| # discard: exprNode |
| # assign: [ node1, ..., nodeN ], exprNode |
| # ass_tuple: [ node1, ..., nodeN ] |
| # ass_list: [ node1, ..., nodeN ] |
| # ass_name: name, flags |
| # ass_attr: exprNode, attrname, flags |
| # list: [ node1, ..., nodeN ] |
| # dict: [ (key1, val1), ..., (keyN, valN) ] |
| # not: exprNode |
| # compare: exprNode, [ (op, node), ..., (op, node) ] |
| # name: name |
| # global: [ name1, ..., nameN ] |
| # backquote: node |
| # getattr: exprNode, attrname |
| # call_func: node, [ arg1, ..., argN ] |
| # keyword: name, exprNode |
| # subscript: exprNode, flags, [ sub1, ..., subN ] |
| # ellipsis: |
| # sliceobj: [ node1, ..., nodeN ] |
| # slice: exprNode, flags, lowerNode, upperNode |
| # assert: expr1, expr2 |
| # |
| # Compiled as "binary" ops: |
| # tuple: [ node1, ..., nodeN ] |
| # or: [ node1, ..., nodeN ] |
| # and: [ node1, ..., nodeN ] |
| # bitor: [ node1, ..., nodeN ] |
| # bitxor: [ node1, ..., nodeN ] |
| # bitand: [ node1, ..., nodeN ] |
| # |
| # Operations easily evaluateable on constants: |
| # <<: exprNode, shiftNode |
| # >>: exprNode, shiftNode |
| # +: leftNode, rightNode |
| # -: leftNode, rightNode |
| # *: leftNode, rightNode |
| # /: leftNode, rightNode |
| # %: leftNode, rightNode |
| # power: leftNode, rightNode |
| # unary+: node |
| # unary-: node |
| # invert: node |
| # |
| |
| """Parse tree transformation module. |
| |
| Exposes the Transformer class with a number of methods for returning a |
| "cleansed AST" instead of the parse tree that the parser exposes. |
| """ |
| |
| import ast |
| import parser |
| import symbol |
| import token |
| import string |
| |
| import pprint |
| |
| error = 'walker.error' |
| |
| from consts import CO_VARARGS, CO_VARKEYWORDS |
| from consts import OP_ASSIGN, OP_DELETE, OP_APPLY |
| |
| 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 ast.nodes.has_key(kind): |
| try: |
| return apply(ast.nodes[kind], args[1:]) |
| except TypeError: |
| print ast.nodes[kind], len(args), args |
| raise |
| else: |
| raise error, "Can't find appropriate Node type." |
| #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) |
| |
| def transform(self, tree): |
| """Transform an AST into a modified parse tree.""" |
| if type(tree) != type(()) and type(tree) != type([]): |
| tree = parser.ast2tuple(tree,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. |
| text = string.replace(text, '\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.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 Node('pass') |
| |
| def file_input(self, nodelist): |
| doc = self.get_docstring(nodelist, symbol.file_input) |
| stmts = [ ] |
| for node in nodelist: |
| if node[0] != token.ENDMARKER and node[0] != token.NEWLINE: |
| self.com_append_stmt(stmts, node) |
| return Node('module', doc, Node('stmt', stmts)) |
| |
| def eval_input(self, nodelist): |
| # from the built-in function input() |
| ### is this sufficient? |
| return 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]) |
| |
| n = Node('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 = Node('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]) |
| |
| n = Node('classdef', 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 Node('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): |
| # testlist ('=' testlist)* |
| exprNode = self.com_node(nodelist[-1]) |
| if len(nodelist) == 1: |
| return Node('discard', exprNode) |
| nodes = [ ] |
| for i in range(0, len(nodelist) - 2, 2): |
| nodes.append(self.com_assign(nodelist[i], OP_ASSIGN)) |
| n = Node('assign', nodes, exprNode) |
| n.lineno = nodelist[1][2] |
| return n |
| |
| def print_stmt(self, nodelist): |
| # print: (test ',')* [test] |
| items = [ ] |
| for i in range(1, len(nodelist), 2): |
| items.append(self.com_node(nodelist[i])) |
| if nodelist[-1][0] == token.COMMA: |
| n = Node('print', items) |
| n.lineno = nodelist[0][2] |
| return n |
| n = Node('printnl', items) |
| 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): |
| # pass: |
| n = Node('pass') |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def break_stmt(self, nodelist): |
| # break: |
| n = Node('break') |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def continue_stmt(self, nodelist): |
| # continue |
| n = Node('continue') |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def return_stmt(self, nodelist): |
| # return: [testlist] |
| if len(nodelist) < 2: |
| n = Node('return', Node('const', None)) |
| n.lineno = nodelist[0][2] |
| return n |
| n = Node('return', 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 = Node('raise', expr1, expr2, expr3) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| def import_stmt(self, nodelist): |
| # import: dotted_name (',' dotted_name)* | |
| # from: dotted_name 'import' ('*' | NAME (',' NAME)*) |
| names = [ ] |
| if nodelist[0][1][0] == 'f': |
| for i in range(3, len(nodelist), 2): |
| # note: nodelist[i] could be (token.STAR, '*') or (token.NAME, name) |
| names.append(nodelist[i][1]) |
| n = Node('from', self.com_dotted_name(nodelist[1]), names) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| for i in range(1, len(nodelist), 2): |
| names.append(self.com_dotted_name(nodelist[i])) |
| n = Node('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 = Node('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 = Node('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 = Node('name', 'None') |
| n = Node('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 = Node('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 = Node('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 = Node('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 Node('stmt', stmts) |
| |
| # -------------------------------------------------------------- |
| # |
| # EXPRESSION NODES (invoked by com_node()) |
| # |
| |
| def testlist(self, nodelist): |
| # testlist: expr (',' expr)* [','] |
| # exprlist: expr (',' expr)* [','] |
| return self.com_binary('tuple', nodelist) |
| |
| exprlist = testlist |
| |
| 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 = Node('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 = 'notin' |
| else: |
| type = 'isnot' |
| 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 = Node('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 = Node('<<', [node, right]) |
| node.lineno = nodelist[1][2] |
| else: |
| node = Node('>>', [node, right]) |
| node.lineno = nodelist[1][2] |
| 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 = Node('+', [node, right]) |
| node.lineno = nodelist[1][2] |
| else: |
| node = Node('-', [node, right]) |
| node.lineno = nodelist[1][2] |
| 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]) |
| if nodelist[i-1][0] == token.STAR: |
| node = Node('*', [node, right]) |
| node.lineno = nodelist[1][2] |
| elif nodelist[i-1][0] == token.SLASH: |
| node = Node('/', [node, right]) |
| node.lineno = nodelist[1][2] |
| else: |
| node = Node('%', [node, right]) |
| node.lineno = nodelist[1][2] |
| return node |
| |
| def factor(self, nodelist): |
| t = nodelist[0][0] |
| node = self.com_node(nodelist[-1]) |
| if t == token.PLUS: |
| node = Node('unary+', node) |
| node.lineno = nodelist[0][2] |
| elif t == token.MINUS: |
| node = Node('unary-', node) |
| node.lineno = nodelist[0][2] |
| elif t == token.TILDE: |
| node = Node('invert', node) |
| node.lineno = nodelist[0][2] |
| return node |
| |
| def power(self, nodelist): |
| # power: atom trailer* ('**' factor)* |
| node = self.com_node(nodelist[0]) |
| for i in range(1, len(nodelist)): |
| if nodelist[i][0] == token.DOUBLESTAR: |
| n = Node('power', [node, self.com_node(nodelist[i+1])]) |
| n.lineno = nodelist[i][2] |
| return n |
| |
| node = self.com_apply_trailer(node, nodelist[i]) |
| |
| return node |
| |
| def atom(self, nodelist): |
| t = nodelist[0][0] |
| if t == token.LPAR: |
| if nodelist[1][0] == token.RPAR: |
| n = Node('const', ()) |
| n.lineno = nodelist[0][2] |
| return n |
| return self.com_node(nodelist[1]) |
| |
| if t == token.LSQB: |
| if nodelist[1][0] == token.RSQB: |
| n = Node('const', [ ]) |
| n.lineno = nodelist[0][2] |
| return n |
| return self.com_list_constructor(nodelist[1]) |
| |
| if t == token.LBRACE: |
| if nodelist[1][0] == token.RBRACE: |
| return Node('const', { }) |
| return self.com_dictmaker(nodelist[1]) |
| |
| if t == token.BACKQUOTE: |
| n = Node('backquote', self.com_node(nodelist[1])) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| if t == token.NUMBER: |
| ### need to verify this matches compile.c |
| k = eval(nodelist[0][1]) |
| n = Node('const', k) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| if t == token.STRING: |
| ### need to verify this matches compile.c |
| k = '' |
| for node in nodelist: |
| k = k + eval(node[1]) |
| n = Node('const', k) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| if t == token.NAME: |
| ### any processing to do? |
| n = Node('name', nodelist[0][1]) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| raise error, "unknown node type" |
| |
| # -------------------------------------------------------------- |
| # |
| # INTERNAL PARSING UTILITIES |
| # |
| |
| 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. |
| |
| # |
| # A ';' at the end of a line can make a NEWLINE token appear here, |
| # Render it harmless. (genc discards ('discard', ('const', xxxx)) Nodes) |
| # |
| if node[0] == token.NEWLINE: |
| return Node('discard', Node('const', None)) |
| |
| if node[0] not in _legal_node_types: |
| raise error, 'illegal node passed to com_node: %s' % node[0] |
| |
| return self._dispatch[node[0]](node[1:]) |
| |
| def com_arglist(self, nodelist): |
| # varargslist: |
| # (fpdef ['=' test] ',')* ('*' NAME [',' ('**'|'*' '*') NAME] |
| # | fpdef ['=' test] (',' fpdef ['=' test])* [','] |
| # | ('**'|'*' '*') NAME) |
| # 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 or STAR STAR |
| if nodelist[i][0] == token.DOUBLESTAR: |
| node = nodelist[i+1] |
| else: |
| node = nodelist[i+2] |
| 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(Node('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_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 = Node('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 = Node('tryexcept', self.com_node(nodelist[2]), clauses, elseNode) |
| n.lineno = nodelist[0][2] |
| return n |
| |
| 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 Node('ass_tuple', assigns) |
| |
| def com_assign_list(self, node, assigning): |
| assigns = [ ] |
| for i in range(1, len(node), 2): |
| assigns.append(self.com_assign(node[i], assigning)) |
| return Node('ass_list', assigns) |
| |
| def com_assign_name(self, node, assigning): |
| return Node('ass_name', node[1], assigning) |
| |
| def com_assign_trailer(self, primary, node, assigning): |
| t = node[1][0] |
| if t == token.LPAR: |
| raise SyntaxError, "can't assign to function call" |
| 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) |
| raise SyntaxError, "unknown trailer type: %s" % t |
| |
| def com_assign_attr(self, primary, node, assigning): |
| return Node('ass_attr', primary, node[1], assigning) |
| |
| def com_binary(self, type, nodelist): |
| "Compile 'NODE (OP NODE)*' into (type, [ node1, ..., nodeN ])." |
| if len(nodelist) == 1: |
| return self.com_node(nodelist[0]) |
| items = [ ] |
| for i in range(0, len(nodelist), 2): |
| items.append(self.com_node(nodelist[i])) |
| return Node(type, items) |
| |
| def com_stmt(self, node): |
| #pprint.pprint(node) |
| result = self.com_node(node) |
| try: |
| result[0] |
| except: |
| print node[0] |
| if result[0] == 'stmt': |
| return result |
| return Node('stmt', [ result ]) |
| |
| def com_append_stmt(self, stmts, node): |
| result = self.com_node(node) |
| try: |
| result[0] |
| except: |
| print node |
| if result[0] == 'stmt': |
| stmts[len(stmts):] = result[1] |
| else: |
| stmts.append(result) |
| |
| def com_list_constructor(self, nodelist): |
| values = [ ] |
| for i in range(1, len(nodelist), 2): |
| values.append(self.com_node(nodelist[i])) |
| return Node('list', values) |
| |
| 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 Node('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 = Node('getattr', primaryNode, nodelist[1]) |
| n.lineno = nodelist[2] |
| return n |
| |
| def com_call_function(self, primaryNode, nodelist): |
| if nodelist[0] == token.RPAR: |
| return Node('call_func', primaryNode, [ ]) |
| args = [ ] |
| kw = 0 |
| for i in range(1, len(nodelist), 2): |
| kw, result = self.com_argument(nodelist[i], kw) |
| args.append(result) |
| return Node('call_func', primaryNode, args) |
| |
| def com_argument(self, nodelist, kw): |
| 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] |
| n = Node('keyword', n[1], result) |
| n.lineno = result.lineno |
| return 1, n |
| |
| 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 Node('subscript', primary, assigning, subscripts) |
| |
| def com_subscript(self, node): |
| # slice_item: expression | proper_slice | ellipsis |
| ch = node[1] |
| if ch[0] == token.DOT and node[2][0] == token.DOT: |
| return ('ellipsis', None) |
| if ch[0] == 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(Node('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(Node('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(Node('const', None)) |
| else: |
| items.append(self.com_node(ch[2])) |
| |
| return Node('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 Node('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.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.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, |
| ] |
| |
| _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, |
| ] |
| |
| # Local Variables: |
| # mode: python |
| # indent-tabs-mode: nil |
| # py-indent-offset: 2 |
| # py-smart-indentation: nil |
| # End: |
| |