首先，如果你想写一个block，像这样:

if statement:
    pass
for i in range(abc):
    pass
def func():
    pass

pass can是一个占位符。

其次，它可以让你与IDE“交流”: 当你想让你的IDE像这样递减缩进: 如果你的程序写在这里:

class abc(parent):
    def __init__(self, params):
        self.params=params
        if d:
            return
        else:
            return
        # cursor in there

现在你的缩进计数是2，但你希望它在下一行是1。 你可以输入一个pass，你的程序是这样的:

class abc(parent):
    def __init__(self, params):
        self.params=params
        if d:
            return
        else:
            return
        pass# cursor in there

并返回。它会让你快乐:

class abc(parent):
    def __init__(self, params):
        self.params=params
        if d:
            return
        else:
            return
        pass
    # cursor in there

现在缩进计数是1。

Pass is usually helpful when you are writing code to design a game or something of that type , now as you proceed with the code , you would realize that , there are some functions you don't want to move ahead and want to leave it untouched and move further on with the code and then revisit the function later , but as you do so , the compiler would obviously thrown an error saying it isn't either recognized and all sorts of other things!! In this condition you use pass so that the compiler would simply neglect the function and move further on with the code !!

例如:

if __name__ = "__main__":
pass
print("Hello World!")

在这里，编译器将忽略if name部分，并按照指示打印Hello World !!

谢谢!

假设您正在设计一个新类，其中包含一些您还不想实现的方法。

class MyClass(object):
    def meth_a(self):
        pass

    def meth_b(self):
        print "I'm meth_b"

如果您省略了传递，代码将无法运行。

然后你会得到一个:

IndentationError: expected an indented block

总之，pass语句不做任何特殊的事情，但它可以充当占位符，如下所示。

首先，如果你想写一个block，像这样:

if statement:
    pass
for i in range(abc):
    pass
def func():
    pass

pass can是一个占位符。

其次，它可以让你与IDE“交流”: 当你想让你的IDE像这样递减缩进: 如果你的程序写在这里:

class abc(parent):
    def __init__(self, params):
        self.params=params
        if d:
            return
        else:
            return
        # cursor in there

现在你的缩进计数是2，但你希望它在下一行是1。 你可以输入一个pass，你的程序是这样的:

class abc(parent):
    def __init__(self, params):
        self.params=params
        if d:
            return
        else:
            return
        pass# cursor in there

并返回。它会让你快乐:

class abc(parent):
    def __init__(self, params):
        self.params=params
        if d:
            return
        else:
            return
        pass
    # cursor in there

现在缩进计数是1。

老实说，我认为Python官方文档描述得很好，并提供了一些示例:

The pass statement does nothing. It can be used when a statement is required syntactically but the program requires no action. For example: >>> while True: ... pass # Busy-wait for keyboard interrupt (Ctrl+C) ... This is commonly used for creating minimal classes: >>> class MyEmptyClass: ... pass ... Another place pass can be used is as a place-holder for a function or conditional body when you are working on new code, allowing you to keep thinking at a more abstract level. The pass is silently ignored: >>> def initlog(*args): ... pass # Remember to implement this! ...

除了“我不想要任何东西到这里”的“主要”用途之外，我刚刚发现了一个，假设gen是一个迭代器:

i = 0
obj = None

for i, obj in enumerate(gen):
    pass

这将在一次传递中获得gen生成的最后一个对象和gen的长度。(有点类似于C语言中以分号结尾的while循环，仔细想想吧。)