我们从Python开源项目中，提取了以下11个代码示例，用于说明如何使用_ast.For()。
def semicolon(self, stmt): if not isinstance(stmt, _ast.If) and not isinstance(stmt, _ast.While) and not isinstance(stmt, _ast.For): return ";" else: return ""
def addBinding(self, node, value): """ Called when a binding is altered. - `node` is the statement responsible for the change - `value` is the new value, a Binding instance """ # assert value.source in (node, node.parent): for scope in self.scopeStack[::-1]: if value.name in scope: break existing = scope.get(value.name) if existing and not self.differentForks(node, existing.source): parent_stmt = self.getParent(value.source) if isinstance(existing, Importation) and isinstance(parent_stmt, ast.For): self.report(messages.ImportShadowedByLoopVar, node, value.name, existing.source) elif scope is self.scope: if (isinstance(parent_stmt, ast.comprehension) and not isinstance(self.getParent(existing.source), (ast.For, ast.comprehension))): self.report(messages.RedefinedInListComp, node, value.name, existing.source) elif not existing.used and value.redefines(existing): self.report(messages.RedefinedWhileUnused, node, value.name, existing.source) elif isinstance(existing, Importation) and value.redefines(existing): existing.redefined.append(node) if value.name in self.scope: # then assume the rebound name is used as a global or within a loop value.used = self.scope[value.name].used self.scope[value.name] = value
def handleNodeStore(self, node): name = getNodeName(node) if not name: return # if the name hasn't already been defined in the current scope if isinstance(self.scope, FunctionScope) and name not in self.scope: # for each function or module scope above us for scope in self.scopeStack[:-1]: if not isinstance(scope, (FunctionScope, ModuleScope)): continue # if the name was defined in that scope, and the name has # been accessed already in the current scope, and hasn't # been declared global used = name in scope and scope[name].used if used and used[0] is self.scope and name not in self.scope.globals: # then it's probably a mistake self.report(messages.UndefinedLocal, scope[name].used[1], name, scope[name].source) break parent_stmt = self.getParent(node) if isinstance(parent_stmt, (ast.For, ast.comprehension)) or ( parent_stmt != node.parent and not self.isLiteralTupleUnpacking(parent_stmt)): binding = Binding(name, node) elif name == '__all__' and isinstance(self.scope, ModuleScope): binding = ExportBinding(name, node.parent, self.scope) else: binding = Assignment(name, node) self.addBinding(node, binding)
def for_loop(self, loop_block): iter_block, _, body_else_block = split(loop_block, 'GET_ITER') # for_iter = body_else_block[0] for_iter = body_else_block.pop(0) assert for_iter.opname == 'FOR_ITER' idx = find_index(body_else_block, lambda instr: instr.opname == 'POP_BLOCK' and for_iter.to == instr.i) assert idx is not False body_block = body_else_block[:idx] else_block = body_else_block[idx + 1:] jump_abs = body_block.pop() assert jump_abs.opname == 'JUMP_ABSOLUTE' and jump_abs.to == for_iter.i iter_stmnt = self.decompile_block(iter_block).stmnt() assert len(iter_stmnt) == 1 iter_stmnt = iter_stmnt[0] body_lst = self.decompile_block(body_block[:], stack_items=[None], jump_map={for_iter.i:for_iter.to}).stmnt() assign_ = body_lst.pop(0) body = body_lst if len(else_block) == 0: else_ = [] else: else_ = self.decompile_block(else_block[:]).stmnt() assign = assign_.targets[0] for_ = _ast.For(target=assign, iter=iter_stmnt, body=body, orelse=else_, lineno=iter_stmnt.lineno, col_offset=0) self.ast_stack.append(for_)
def checkDeadScopes(self): """ Look at scopes which have been fully examined and report names in them which were imported but unused. """ for scope in self.deadScopes: if isinstance(scope.get('__all__'), ExportBinding): all_names = set(scope['__all__'].names) if not scope.importStarred and \ os.path.basename(self.filename) != '__init__.py': # Look for possible mistakes in the export list undefined = all_names.difference(scope) for name in undefined: self.report(messages.UndefinedExport, scope['__all__'].source, name) else: all_names = [] # Look for imported names that aren't used. for value in scope.values(): if isinstance(value, Importation): used = value.used or value.name in all_names if not used: messg = messages.UnusedImport self.report(messg, value.source, value.name) for node in value.redefined: if isinstance(self.getParent(node), ast.For): messg = messages.ImportShadowedByLoopVar elif used: continue else: messg = messages.RedefinedWhileUnused self.report(messg, node, value.name, value.source)
def checkDeadScopes(self): """ Look at scopes which have been fully examined and report names in them which were imported but unused. """ for scope in self.deadScopes: # imports in classes are public members if isinstance(scope, ClassScope): continue all_binding = scope.get('__all__') if all_binding and not isinstance(all_binding, ExportBinding): all_binding = None if all_binding: all_names = set(all_binding.names) undefined = all_names.difference(scope) else: all_names = undefined = [] if undefined: if not scope.importStarred and \ os.path.basename(self.filename) != '__init__.py': # Look for possible mistakes in the export list for name in undefined: self.report(messages.UndefinedExport, scope['__all__'].source, name) # mark all import '*' as used by the undefined in __all__ if scope.importStarred: for binding in scope.values(): if isinstance(binding, StarImportation): binding.used = all_binding # Look for imported names that aren't used. for value in scope.values(): if isinstance(value, Importation): used = value.used or value.name in all_names if not used: messg = messages.UnusedImport self.report(messg, value.source, str(value)) for node in value.redefined: if isinstance(self.getParent(node), ast.For): messg = messages.ImportShadowedByLoopVar elif used: continue else: messg = messages.RedefinedWhileUnused self.report(messg, node, value.name, value.source)
