I have one defined function and I would like to define another one which is exactly the same as the first, but specifying one parameter.
One possible way of doing that is
def my_function(arg1, arg2):
print(arg1, arg2)
def my_function_foo(arg1):
return(my_function(arg1, 'bar'))
>>> my_function_foo('foo')
foo bar
But I suppose there is a cleaner way, closer to:
my_function_foo = my_function(arg2 = 'foo')
Use functools.partial:
>>> from functools import partial
>>> my_function_foo = partial(my_function, arg2='bar')
>>> my_function_foo('foo')
foo bar
Note that my_function_foo is not technically a function, but an instance of partial. Calling the instance calls the underlying function using the previously given and current arguments merged in the expected way.
You can create a decorator that will pass the parameter for you.
from functools import wraps
def give_param(param='bar'):
def inner_function(func):
@wraps(func)
def wrapper(*args, **kwargs):
return func(*args, arg2=param)
return wrapper
return inner_function
@give_param('bar')
def my_function(arg1,arg2):
# do some stuff
print(arg1,arg2)
So if you want arg2 = 3,
@give_param(3)
def my_function(arg1,arg2):
# do some stuff
print(arg1,arg2)
You could use the multiple dispatch library to do a method override like in C:
from multipledispatch import dispatch
@dispatch(object, object)
def my_function(arg1, arg2):
print(arg1, arg2)
@dispatch(object)
def my_function(arg1):
return(my_function(arg1, 'bar'))
my_function('foo')
my_function('foo', 'foo')
You might solve your problem with an inner function as follows:
def my_function(arg1, arg2='bar'):
def my_function_foo(arg1):
print(arg1, arg2)
return my_function_foo(arg1)
my_function(arg1 = 'foo')
barforarg2, one that assumes a value of3, etc.