Advanced Lesson 4
Python Decorators
Chapter 2: Python decorators
Decorators with parameters
What if our decorator itself needs some arguments? For example, I might want to allow the decorator to repeat a function an arbitrary number of times.
Well, that requires a bit more work. You will have to wrap your decorator further in another function. Don’t worry too much about this one - you will unlikely need to do this! (My head is spinning too!)
def n_repeat(times):
def repeat(func):
def wrapper(*args, **kwargs):
for i in range(times):
func(*args, **kwargs)
return wrapper
return repeat
@n_repeat(5) # Pass in times as argument
def greet(message, firstname, lastname):
print(f"{message}, {firstname} {lastname}!")
@n_repeat(times=3) # You can also use keyword arguments
def sing(line):
print(line)
sing("We wish you a Merry Christmas...")
greet("Happy New Year", "Josiah", "Wang")
print(sing) # <function n_repeat.<locals>.repeat.<locals>.wrapper at 0x7f9e0198c430>
You should get "We wish you a Merry Christmas..." repeated 3 times, and "Happy New Year, Josiah Wang!" repeated 5 times.