Day11-python Foundation

Day11

day11 1

1. Application of Function name (first object) 2

1.1. 1, the direct print function name gets the memory address of the function 2

1.2. 2, function name can be assigned a value Operation 2

1.3. 3, function name can be used as parameter of function 2

1.4. 4, the function name can be used as an element of the container class data type 2

1.5. function names can be used as return values for functions 2

2. Closure Pack 2

2.1. inner function A reference to a non-global variable of outer layer function is called closure 3

2.2. judgment is the name of the closure function. __closure__ 3

2.2.1. None returned is not a closure, the cell is returned .... Is the closure 3

2.3. What's the use of closures? 3

2.3.1. when executing a function, if the interpreter determines that the inner closure of this function exists, Python has a mechanism where the temporary namespace of the closure does not disappear as the function finishes executing. 3

3. Adorner 3

3.1. definition and application 4

3.1.1. adorners are essentially a Python function that allows other functions to add additional functionality without any code changes, and the return value of the adorner is also a function object. 4

3.1.2. Adorner application scenarios: such as inserting logs, performance tests, transaction processing, caching, and so on. 4

3.2. simple to enter and multiply 4

3.2.1. Starter Decorators 4

3.2.2. Syntax sugar 5

3.2.3. Adorner with parameters 5

3.2.4. holding the adorner for all parameters 6

2. function name Application (first object)
   1. Span style= "FONT-FAMILY:CALIBRI; Font-size:12pt ">1, the direct print function name gets the memory address of the function
   2. 2, the function name can be assigned a value operation
   3. 3, function name can be a parameter of the function
   4. Span style= "FONT-FAMILY:CALIBRI; Font-size:12pt ">4, the function name can be an element of the container class data type
4. Closed Package
   1. Inner layer function The reference to the non-global variable of the outer layer function is called the closure packet
   2. The judgment is the name of the closure function. __closure__
   1. None returned is not a closure, the cell is returned .... It's a closed packet.
   1. What's the use of closures?
   1. When executing a function, if the interpreter determines that the inner closure of this function exists, Python has a mechanism where the temporary namespace of the closure does not disappear as the function finishes executing.
5. Decorative Device
   1. Definition and application
   1. The adorner is essentially a Python function that allows other functions to add additional functionality without any code changes, and the return value of the adorner is also a function object.
   2. Application scenarios for adorners: such as inserting logs, performance tests, transaction processing, caching, and so on.
   1. Simple to enter and multiply
   1. Starter Decorators

      Import time

      Def func1 ():

      Print (' in func1 ')

      def timer (func):

      def inner ():

      Start = Time.time ()

      Func ()

      Print (Time.time ()-start)

      return inner

      FUNC1 = Timer (func1)

      Func1 ()

      Decorator---simple version

   2. Grammar Sugar

      Import time

      def timer (func):

      def inner ():

      Start = Time.time ()

      Func ()

      Print (Time.time ()-start)

      return inner

      @timer #==> func1 = Timer (func1)

      Def func1 ():

      Print (' in func1 ')

      Func1 ()

      Decorator---grammar sugar

   3. Adorner with Parameters

      def timer (func):

      def inner (a):

      Start = Time.time ()

      Func (a)

      Print (Time.time ()-start)

      return inner

      @timer

      Def func1 (a):

      Print (a)

      FUNC1 (1)

      Adorner--an adorner with parameters

   4. the adorner holding all parameters

      Import time

      def timer (func):

      def inner (*args,**kwargs):

      Start = Time.time ()

      Re = func (*args,**kwargs)

      Print (Time.time ()-start)

      return re

      return inner

      @timer #==> func1 = Timer (func1)

      Def func1 (A, B):

      Print (' in func1 ')

      @timer #==> Func2 = Timer (FUNC2)

      Def Func2 (a):

      Print (' In Func2 and get a:%s '% (a))

      Return ' fun2 over '

      Func1 (' aaaaaa ', ' bbbbbb ')

      Print (Func2 (' aaaaaa '))

      Adorner---Hold all parameters of the adorner

Day11-python Foundation