table of Contents

A variable length parameter

* Katachisan

The function is called, the receiving position of excess tuple argument

def f1 (* args): args to do with the general convention parameter variable name
Print (args)

** Katachisan

When you call the function, receiving extra keyword arguments dictionary

def f1 (** kwargs): # convention generally do with kwargs * parameter variable name
print (kwargs)

*Arguments

When the parameter passing, the elements in the list and then broken into position successively passed argument position parameter

def f1(a, b, c, e, d, f, g):
print(a, b, c, e, d, f, g)
lt = [1, 2, 3, 4, 5, 6, 7]
f1(*lt)

**Arguments

When the parameter passing, the dictionary elements broken into Keyword argument followed position parameter passed

def f1(z, b):
print(z, b)

dic = {'z': 1, 'b': 2} # a=1,b=2
f1(**dic)

Second, the function object

Everything in python objects

It is also a function of the object

Function object function name =

+ Function name () that is called, is calling

Reference (copy)

def f1():
    print('from f1')  

func = f1
print('f1:', f1)
print('func:', func)

func()

Container element

def f1():
    print('from f1')

lt = [f1, 1, 2, 3]

print('lt[0]', lt[0])
print('f1', f1)

lt[0]()

As the argument of function

def f1():
    print('from f1')   

def f2(f2_f1):
    print('f2_f1',f2_f1)
    f2_f1()

f2(f1)

As the return value of the function

def f1():
    print('from f1')     

def f2(f2_f1):
    return f2_f1


res = f2(f1)  # 即res = f1
print('res', res)
print('f1', f1)

res()

Third, nested functions

Nested functions: a function which has the function

Defining a function, only detect syntax, the code will not be executed

Internal function defined functions, can not be used outside

Fourth, namespace and scope

Namespace executed (generated) sequence

Built-in Built-in namespace: python interpreter starts when there is a
Global name space: time code executable file will have a global
The local name space: time function call will have a local

Search Order

Start looking for the current location, and then can not find in that order, not against the direction of looking

Local - "Global -" Built - "error

Namespaces

Dedicated memory used to store the name space

Built-in namespace

Storage space in the name of the built-in method

Global name space

In addition to the built-in global and local call

The local name space

Local call within the function definitions

Scope

Global scope

Built-in namespace = + global namespace global scope

Local scope

Local local scope namespace =

Features local scope

Global scope and local scope x x relationship is not half dime
Local scope x 1 x 2 and the local scope is also no relationship, then the two even with a local scope, and a local scope local scope

day11 summary