A simple file giving examples for creating decorator functions

python_decorators.py

# decorators are just shorthand for passing functions as arguments to other functions

# They are called decorators as code can be run before and after the supplied
# function is run (if at all). A good use for decorator functions is adding
# callback hooks for your applications. The decorator functions take the
# supplied function and store it to be run at the right time

# There are two types of decorators: regular decorator and callable decorators

# regular decorators take the function it's decorating as an argument
# this is best if no extra arguments need to be given in the decoration process
def decorator(decorated_function):
    print("hello")
    decorated_function()
    print("!")

@decorator
def world():
    print("world")

# callable decorators return a function that is called once returned
# this is userful if you need to pass arguments to the decoration process
def callable_decorator(before_text):
    # define returned function
    def decorate(decorated_function):
        # execute decorated
        decorated_function()
        # do things after decoration here
        print("!")
    # do things before executing the returned function here
    print(before_text)
    # returned decorate function
    return decorate

@callable_decorator("hello")
def world_2():
    print("world")

"""
hello                   # line 8
world                   # line 14
!                       # line 10
hello                   # line 26
world                   # line 32
!                       # line 24
"""