python - 如何在另一个函数中调用函数？

Question

如果我有两个函数，(一个在另一个里面)；

def test1():
    def test2():
        print("test2")

如何调用test2？

Answer 1

也可以这样调用:

def test1():
    text = "Foo is pretty"
    print "Inside test1()"
    def test2():
        print "Inside test2()"
        print "test2() -> ", text
    return test2

test1()() # first way, prints "Foo is pretty"

test2 = test1() # second way
test2() # prints "Foo is pretty"

让我们看看:

>>> Inside test1()
>>> Inside test2()
>>> test2() ->  Foo is pretty

>>> Inside test1()
>>> Inside test2()
>>> test2() ->  Foo is pretty

如果你不想调用 test2():

test1() # first way, prints "Inside test1()", but there's test2() as return value.
>>> Inside test1()
print test1()
>>> <function test2 at 0x1202c80>

让我们更加努力:

def test1():
    print "Inside test1()"
    def test2():
        print "Inside test2()"
        def test3():
            print "Inside test3()"
            return "Foo is pretty."
        return test3
    return test2

print test1()()() # first way, prints the return string "Foo is pretty."

test2 = test1() # second way
test3 = test2()
print test3() # prints "Foo is pretty."

让我们看看:

>>> Inside test1()
>>> Inside test2()
>>> Inside test3()
>>> Foo is pretty.

>>> Inside test1()
>>> Inside test2()
>>> Inside test3()
>>> Foo is pretty.