expr.py 文件源码

def visit_Compare(self, node, **kwargs):
        ops = node.ops
        comps = node.comparators

        # base case: we have something like a CMP b
        if len(comps) == 1:
            op = self.translate_In(ops[0])
            binop = ast.BinOp(op=op, left=node.left, right=comps[0])
            return self.visit(binop)

        # recursive case: we have a chained comparison, a CMP b CMP c, etc.
        left = node.left
        values = []
        for op, comp in zip(ops, comps):
            new_node = self.visit(ast.Compare(comparators=[comp], left=left,
                                              ops=[self.translate_In(op)]))
            left = comp
            values.append(new_node)
        return self.visit(ast.BoolOp(op=ast.And(), values=values))