Is it possible to trigger the default keywork argument of a function in some special cases ? In particular in this example:
def funcA(a, data='dataset1'):
... # function code
def funcB(a, b, c, data='dataset42'):
... # function code
def func_global(a, b, c, data):
funcA(a, data=data)
funcB(a, b, c, data=data)
# standard use, funcA and funcB use dataset5
func_global(1,2,3, data='dataset5')
# desired use : funcA and funcB use the dataset from their default kwarg
func_global(1,2,3, data='default') # this obviously wont work as will call the dataset called 'default'
# what I want to avoid because I have a lot of functions (A,B,C,...), and I don't want to duplicate:
def func_global(a, b, c, data):
if data == 'default':
funcA(a)
funcB(a, b, c)
else:
funcA(a, data=data)
funcB(a, b, c, data=data)
Also a constraint: I cannot change the funcA or funcB. if you have any suggestion how to avoid the duplication, thanks a lot
Answer
You can use a decorator:
def default_data(func):
def f(*args, **kwargs):
if 'data' in kwargs and kwargs['data'] == 'default':
del kwargs['data']
return func(*args, **kwargs)
return f
Now you need to decorate your functions and simplify func_global
funcA = default_data(funcA)
funcB = default_data(funcB)
def func_global(a, b, c, data):
funcA(a, data=data)
funcB(a, b, c, data=data)
If you have access to the code of funcA and funcB then you can simply decorate them with @default_data:
@default_data
def funcA(a, data='dataset1'):
... # function code
@default_data
def funcB(a, b, c, data='dataset42'):
... # function code