Example of a function (closure) usage in a Python function

The examples in this article describe the use of Python closures. Share to everyone for your reference, as follows:

Functions can also be defined in Python functions, i.e. closures. In fact, the concept of closure in JS is about the same as in the case of a python closure.

def make_adder (addend):  def adder (augend):    return augend + addend  return adderp = Make_adder (all) Q = Make_ Adder (+) print (P (+)) print (q (100))

The results are: 123 and 144.

Why? In Python all objects, execute P (100), where P is make_adder (23) This object, that is, addend this parameter is 23, you pass in a 100, that is, the Augend parameter is 100, the two add 123 and return.

Did you find make_adder this function, which defines a closure function, but the return returned by Make_adder is the name of the closure function inside, which is the feature of the closure function.

Let's look at a python closure example:

def hellocounter (name):  count=[0]  def counter ():    count[0]+=1    print (' Hello, ', Name, ', ', count[0], ' Access! ')  return Counterhello = Hellocounter (' ma6174 ') hello () hello () hello ()

Operation Result:

Tantengdemacbook-pro:learn-python tanteng$ python3 closure.py Hello, ma6174, 1 access! Hello, ma6174, 2 access! Hello, ma6174, 3 access!

The use of closures to implement the function of the counter, which is a feature of closures, the returned value is stored in memory, so you can implement the Count function.

Turn from: Small Talk blog http://www.tantengvip.com/2015/07/python-closure/

I hope this article is helpful for Python program design.

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