Recursion & decorators & Regular Operations & modules

Recursion:

def f (a):    if a <:        print (a)        a+=1        B = a        f (b)        return a    else:        return a

A = f (5)

A equals 6 A equals 6 executes once

Attention

How to correctly value?

def f (a):    if a <:        print (a)        a+=1        B = f (a)        f (b)        return b    Else:        return a

The return value is a function, you can.

Adorner:

def outer (func):    def inner (*arg, **kwargs):        print ("content performed before function")        ret = func (*arg, **kwargs)        print ( ' Content executed after function ')        return ret    return Inner@outerdef index (a):    print ("original function")    return True

Just write it.

Adorners can be nested to treat nested functions as a whole

Regular expression

Match matches Start

Search matches from front to back

No result returned none

FindAll matches All

Xxxx.group no results will be an error

Key = Re.search (' \d+\.*\d*[\*\/]+[\+\-]?\d+\.*\d* ', Val)    if  key

This is the decision to get the value and then operate

Recursion & decorators & Regular Operations & modules