C-like assignment expression?

[Bruno Desthuilliers]

boblatest at googlemail.com a écrit :
> Hello,
> 
> I have an if-elif chain in which I'd like to match a string against
> several regular expressions. Also I'd like to use the match groups
> within the respective elif... block. The C-like idiom that I would
> like to use is this:
> 
> if (match = my_re1.match(line):
>   # use match
> elsif (match = my_re2.match(line)):
>   # use match
> elsif (match = my_re3.match(line))
>   # use match

<ot>
Isn't it the third or fourth time this very same question pops up here ? 
  Starts to look like a FAQ.
</ot>

The canonical solution is to iterate over a list of expression,function 
pairs, ie:

def use_match1(match):
    # code here

def use_match2(match):
    # code here

def use_match3(match):
    # code here

for exp, func in [
     (my_re1, use_match1),
     (my_re2, use_match2),
     (my_re3, use_match3)
     ]:
     match = exp.match(line)
     if match:
        func(match)
        break


The alternate solution is Diez's Test object.

HTH