Question

I have code that looks like this:

if(func_cliche_start(line)):
   a=func_cliche_start(line)
   #... do stuff with 'a' and line here
elif(func_test_start(line)):
   a=func_test_start(line)
   #... do stuff with a and line here
elif(func_macro_start(line)):
   a=func_macro_start(line)
   #... do stuff with a and line here
...

Each of the func_blah_start functions either return None or a string (based on the input line). I don’t like the redundant call to func_blah_start as it seems like a waste (func_blah_start is “pure”, so we can assume no side effects). Is there a better idiom for this type of thing, or is there a better way to do it?

Perhaps I’m wrong, (my C is rusty), but I thought that you could do something this in C:

int a;
if(a=myfunc(input)){ /*do something with a and input here*/ }

is there a python equivalent?

Answer 1

You can create a wrapper function to make this work.

def assign(value, lst):
    lst[0] = value
    return value

a = [None]
if assign(func_cliche_start(line), a):
   #... do stuff with 'a[0]' and line here
elif assign(func_test_start(line), a):
   #...