我们从Python开源项目中，提取了以下25个代码示例，用于说明如何使用symbol.comp_for()。
def com_argument(self, nodelist, kw, star_node): if len(nodelist) == 3 and nodelist[2][0] == symbol.comp_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" if star_node: raise SyntaxError, "only named arguments may follow *expression" 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, lineno=n[2]) return 1, node
def testlist_comp(self, nodelist): # test ( comp_for | (',' test)* [','] ) assert nodelist[0][0] == symbol.test if len(nodelist) == 2 and nodelist[1][0] == symbol.comp_for: test = self.com_node(nodelist[0]) return self.com_generator_expression(test, nodelist[1]) return self.testlist(nodelist)
def com_generator_expression(self, expr, node): # comp_iter: comp_for | comp_if # comp_for: 'for' exprlist 'in' test [comp_iter] # comp_if: 'if' test [comp_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, [], lineno=node[1][2]) fors.append(newfor) if (len(node)) == 5: node = None else: node = self.com_comp_iter(node[5]) elif t == 'if': test = self.com_node(node[2]) newif = GenExprIf(test, lineno=node[1][2]) newfor.ifs.append(newif) if len(node) == 3: node = None else: node = self.com_comp_iter(node[3]) else: raise SyntaxError, \ ("unexpected generator expression element: %s %d" % (node, lineno)) fors[0].is_outmost = True return GenExpr(GenExprInner(expr, fors), lineno=lineno)
def com_dictorsetmaker(self, nodelist): # dictorsetmaker: ( (test ':' test (comp_for | (',' test ':' test)* [','])) | # (test (comp_for | (',' test)* [','])) ) assert nodelist[0] == symbol.dictorsetmaker nodelist = nodelist[1:] if len(nodelist) == 1 or nodelist[1][0] == token.COMMA: # set literal items = [] for i in range(0, len(nodelist), 2): items.append(self.com_node(nodelist[i])) return Set(items, lineno=items[0].lineno) elif nodelist[1][0] == symbol.comp_for: # set comprehension expr = self.com_node(nodelist[0]) return self.com_comprehension(expr, None, nodelist[1], 'set') elif len(nodelist) > 3 and nodelist[3][0] == symbol.comp_for: # dict comprehension assert nodelist[1][0] == token.COLON key = self.com_node(nodelist[0]) value = self.com_node(nodelist[2]) return self.com_comprehension(key, value, nodelist[3], 'dict') else: # dict literal items = [] for i in range(0, len(nodelist), 4): items.append((self.com_node(nodelist[i]), self.com_node(nodelist[i+2]))) return Dict(items, lineno=items[0][0].lineno)
def com_call_function(self, primaryNode, nodelist): if nodelist[0] == token.RPAR: return CallFunc(primaryNode, [], lineno=extractLineNo(nodelist)) args = [] kw = 0 star_node = dstar_node = None len_nodelist = len(nodelist) i = 1 while i < len_nodelist: node = nodelist[i] if node[0]==token.STAR: if star_node is not None: raise SyntaxError, 'already have the varargs indentifier' star_node = self.com_node(nodelist[i+1]) i = i + 3 continue elif node[0]==token.DOUBLESTAR: if dstar_node is not None: raise SyntaxError, 'already have the kwargs indentifier' dstar_node = self.com_node(nodelist[i+1]) i = i + 3 continue # positional or named parameters kw, result = self.com_argument(node, kw, star_node) if len_nodelist != 2 and isinstance(result, GenExpr) \ and len(node) == 3 and node[2][0] == symbol.comp_for: # allow f(x for x in y), but reject f(x for x in y, 1) # should use f((x for x in y), 1) instead of f(x for x in y, 1) raise SyntaxError, 'generator expression needs parenthesis' args.append(result) i = i + 2 return CallFunc(primaryNode, args, star_node, dstar_node, lineno=extractLineNo(nodelist))
