"""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) -> ASTparseFile(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## Some fixes to try to have correct line number on almost all nodes# (except Module, Discard and Stmt) added by Sylvain Thenault## 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 compiler.ast import *import parserimport symbolimport tokenimport sys class WalkerError(StandardError): pass from compiler.consts import CO_VARARGS, CO_VARKEYWORDSfrom compiler.consts import OP_ASSIGN, OP_DELETE, OP_APPLY def parseFile(path): f = open(path, "U") # 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 extractLineNo(ast): if not isinstance(ast[1], tuple): # get a terminal node return ast[2] for child in ast[1:]: if isinstance(child, tuple): lineno = extractLineNo(child) if lineno is not None: return lineno 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 WalkerError, "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 not (isinstance(tree, tuple) or isinstance(tree, list)): 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.""" 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 WalkerError, ('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 decorator_name(self, nodelist): listlen = len(nodelist) assert listlen >= 1 and listlen % 2 == 1 item = self.atom_name(nodelist) i = 1 while i < listlen: assert nodelist[i][0] == token.DOT assert nodelist[i + 1][0] == token.NAME item = Getattr(item, nodelist[i + 1][1]) i += 2 return item def decorator(self, nodelist): # '@' dotted_name [ '(' [arglist] ')' ] assert len(nodelist) in (3, 5, 6) assert nodelist[0][0] == token.AT assert nodelist[-1][0] == token.NEWLINE assert nodelist[1][0] == symbol.dotted_name funcname = self.decorator_name(nodelist[1][1:]) if len(nodelist) > 3: assert nodelist[2][0] == token.LPAR expr = self.com_call_function(funcname, nodelist[3]) else: expr = funcname return expr def decorators(self, nodelist): # decorators: decorator ([NEWLINE] decorator)* NEWLINE items = [] for dec_nodelist in nodelist: assert dec_nodelist[0] == symbol.decorator items.append(self.decorator(dec_nodelist[1:])) return Decorators(items) def funcdef(self, nodelist): # -6 -5 -4 -3 -2 -1 # funcdef: [decorators] 'def' NAME parameters ':' suite # parameters: '(' [varargslist] ')' if len(nodelist) == 6: assert nodelist[0][0] == symbol.decorators decorators = self.decorators(nodelist[0][1:]) else: assert len(nodelist) == 5 decorators = None lineno = nodelist[-4][2] name = nodelist[-4][1] args = nodelist[-3][2] if args[0] == symbol.varargslist: names, defaults, flags = self.com_arglist(args[1:]) else: names = defaults = () flags = 0 doc = self.get_docstring(nodelist[-1]) # code for function 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] return Function(decorators, name, names, defaults, flags, doc, code, lineno=lineno) 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]) return Lambda(names, defaults, flags, code, lineno=nodelist[1][2]) old_lambdef = lambdef 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 = [] elif nodelist[3][0] == token.RPAR: 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] return Class(name, bases, doc, code, lineno=nodelist[1][2]) 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 WalkerError def varargslist(self, nodelist): raise WalkerError def fpdef(self, nodelist): raise WalkerError def fplist(self, nodelist): raise WalkerError def dotted_name(self, nodelist): raise WalkerError def comp_op(self, nodelist): raise WalkerError def trailer(self, nodelist): raise WalkerError def sliceop(self, nodelist): raise WalkerError def argument(self, nodelist): raise WalkerError # -------------------------------------------------------------- # # 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: return Discard(exprNode, lineno=exprNode.lineno) 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)) return Assign(nodesl, exprNode, lineno=nodelist[1][2]) else: lval = self.com_augassign(nodelist[0]) op = self.com_augassign_op(nodelist[1]) return AugAssign(lval, op[1], exprNode, lineno=op[2]) raise WalkerError, "can't get here" 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: return Print(items, dest, lineno=nodelist[0][2]) return Printnl(items, dest, lineno=nodelist[0][2]) def del_stmt(self, nodelist): return self.com_assign(nodelist[1], OP_DELETE) def pass_stmt(self, nodelist): return Pass(lineno=nodelist[0][2]) def break_stmt(self, nodelist): return Break(lineno=nodelist[0][2]) def continue_stmt(self, nodelist): return Continue(lineno=nodelist[0][2]) def return_stmt(self, nodelist): # return: [testlist] if len(nodelist) < 2: return Return(Const(None), lineno=nodelist[0][2]) return Return(self.com_node(nodelist[1]), lineno=nodelist[0][2]) def yield_stmt(self, nodelist): expr = self.com_node(nodelist[0]) return Discard(expr, lineno=expr.lineno) def yield_expr(self, nodelist): if len(nodelist) > 1: value = self.com_node(nodelist[1]) else: value = Const(None) return Yield(value, lineno=nodelist[0][2]) 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 return Raise(expr1, expr2, expr3, lineno=nodelist[0][2]) def import_stmt(self, nodelist): # import_stmt: import_name | import_from assert len(nodelist) == 1 return self.com_node(nodelist[0]) def import_name(self, nodelist): # import_name: 'import' dotted_as_names return Import(self.com_dotted_as_names(nodelist[1]), lineno=nodelist[0][2]) def import_from(self, nodelist): # import_from: 'from' ('.'* dotted_name | '.') 'import' ('*' | # '(' import_as_names ')' | import_as_names) assert nodelist[0][1] == 'from' idx = 1 while nodelist[idx][1] == '.': idx += 1 level = idx - 1 if nodelist[idx][0] == symbol.dotted_name: fromname = self.com_dotted_name(nodelist[idx]) idx += 1 else: fromname = "" assert nodelist[idx][1] == 'import' if nodelist[idx + 1][0] == token.STAR: return From(fromname, [('*', None)], level, lineno=nodelist[0][2]) else: node = nodelist[idx + 1 + (nodelist[idx + 1][0] == token.LPAR)] return From(fromname, self.com_import_as_names(node), level, lineno=nodelist[0][2]) def global_stmt(self, nodelist): # global: NAME (',' NAME)* names = [] for i in range(1, len(nodelist), 2): names.append(nodelist[i][1]) return Global(names, lineno=nodelist[0][2]) 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 return Exec(expr1, expr2, expr3, lineno=nodelist[0][2]) 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 return Assert(expr1, expr2, lineno=nodelist[0][2]) 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])Lines 1–500 of 1490. 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"""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 # # Some fixes to try to have correct line number on almost all nodes # (except Module, Discard and Stmt) added by Sylvain Thenault # # 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 compiler.ast import * import parser import symbol import token import sys class WalkerError(StandardError): pass from compiler.consts import CO_VARARGS, CO_VARKEYWORDS from compiler.consts import OP_ASSIGN, OP_DELETE, OP_APPLY def parseFile(path): f = open(path, "U") # 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 extractLineNo(ast): if not isinstance(ast[1], tuple): # get a terminal node return ast[2] for child in ast[1:]: if isinstance(child, tuple): lineno = extractLineNo(child) if lineno is not None: return lineno 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 WalkerError, "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 not (isinstance(tree, tuple) or isinstance(tree, list)): 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.""" 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 WalkerError, ('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 decorator_name(self, nodelist): listlen = len(nodelist) assert listlen >= 1 and listlen % 2 == 1 item = self.atom_name(nodelist) i = 1 while i < listlen: assert nodelist[i][0] == token.DOT assert nodelist[i + 1][0] == token.NAME item = Getattr(item, nodelist[i + 1][1]) i += 2 return item def decorator(self, nodelist): # '@' dotted_name [ '(' [arglist] ')' ] assert len(nodelist) in (3, 5, 6) assert nodelist[0][0] == token.AT assert nodelist[-1][0] == token.NEWLINE assert nodelist[1][0] == symbol.dotted_name funcname = self.decorator_name(nodelist[1][1:]) if len(nodelist) > 3: assert nodelist[2][0] == token.LPAR expr = self.com_call_function(funcname, nodelist[3]) else: expr = funcname return expr def decorators(self, nodelist): # decorators: decorator ([NEWLINE] decorator)* NEWLINE items = [] for dec_nodelist in nodelist: assert dec_nodelist[0] == symbol.decorator items.append(self.decorator(dec_nodelist[1:])) return Decorators(items) def funcdef(self, nodelist): # -6 -5 -4 -3 -2 -1 # funcdef: [decorators] 'def' NAME parameters ':' suite # parameters: '(' [varargslist] ')' if len(nodelist) == 6: assert nodelist[0][0] == symbol.decorators decorators = self.decorators(nodelist[0][1:]) else: assert len(nodelist) == 5 decorators = None lineno = nodelist[-4][2] name = nodelist[-4][1] args = nodelist[-3][2] if args[0] == symbol.varargslist: names, defaults, flags = self.com_arglist(args[1:]) else: names = defaults = () flags = 0 doc = self.get_docstring(nodelist[-1]) # code for function 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] return Function(decorators, name, names, defaults, flags, doc, code, lineno=lineno) 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]) return Lambda(names, defaults, flags, code, lineno=nodelist[1][2]) old_lambdef = lambdef 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 = [] elif nodelist[3][0] == token.RPAR: 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] return Class(name, bases, doc, code, lineno=nodelist[1][2]) 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 WalkerError def varargslist(self, nodelist): raise WalkerError def fpdef(self, nodelist): raise WalkerError def fplist(self, nodelist): raise WalkerError def dotted_name(self, nodelist): raise WalkerError def comp_op(self, nodelist): raise WalkerError def trailer(self, nodelist): raise WalkerError def sliceop(self, nodelist): raise WalkerError def argument(self, nodelist): raise WalkerError # -------------------------------------------------------------- # # 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: return Discard(exprNode, lineno=exprNode.lineno) 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)) return Assign(nodesl, exprNode, lineno=nodelist[1][2]) else: lval = self.com_augassign(nodelist[0]) op = self.com_augassign_op(nodelist[1]) return AugAssign(lval, op[1], exprNode, lineno=op[2]) raise WalkerError, "can't get here" 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: return Print(items, dest, lineno=nodelist[0][2]) return Printnl(items, dest, lineno=nodelist[0][2]) def del_stmt(self, nodelist): return self.com_assign(nodelist[1], OP_DELETE) def pass_stmt(self, nodelist): return Pass(lineno=nodelist[0][2]) def break_stmt(self, nodelist): return Break(lineno=nodelist[0][2]) def continue_stmt(self, nodelist): return Continue(lineno=nodelist[0][2]) def return_stmt(self, nodelist): # return: [testlist] if len(nodelist) < 2: return Return(Const(None), lineno=nodelist[0][2]) return Return(self.com_node(nodelist[1]), lineno=nodelist[0][2]) def yield_stmt(self, nodelist): expr = self.com_node(nodelist[0]) return Discard(expr, lineno=expr.lineno) def yield_expr(self, nodelist): if len(nodelist) > 1: value = self.com_node(nodelist[1]) else: value = Const(None) return Yield(value, lineno=nodelist[0][2]) 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 return Raise(expr1, expr2, expr3, lineno=nodelist[0][2]) def import_stmt(self, nodelist): # import_stmt: import_name | import_from assert len(nodelist) == 1 return self.com_node(nodelist[0]) def import_name(self, nodelist): # import_name: 'import' dotted_as_names return Import(self.com_dotted_as_names(nodelist[1]), lineno=nodelist[0][2]) def import_from(self, nodelist): # import_from: 'from' ('.'* dotted_name | '.') 'import' ('*' | # '(' import_as_names ')' | import_as_names) assert nodelist[0][1] == 'from' idx = 1 while nodelist[idx][1] == '.': idx += 1 level = idx - 1 if nodelist[idx][0] == symbol.dotted_name: fromname = self.com_dotted_name(nodelist[idx]) idx += 1 else: fromname = "" assert nodelist[idx][1] == 'import' if nodelist[idx + 1][0] == token.STAR: return From(fromname, [('*', None)], level, lineno=nodelist[0][2]) else: node = nodelist[idx + 1 + (nodelist[idx + 1][0] == token.LPAR)] return From(fromname, self.com_import_as_names(node), level, lineno=nodelist[0][2]) def global_stmt(self, nodelist): # global: NAME (',' NAME)* names = [] for i in range(1, len(nodelist), 2): names.append(nodelist[i][1]) return Global(names, lineno=nodelist[0][2]) 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 return Exec(expr1, expr2, expr3, lineno=nodelist[0][2]) 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 return Assert(expr1, expr2, lineno=nodelist[0][2]) 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])