affectation in if statement

Bruno Desthuilliers bruno.42.desthuilliers at websiteburo.invalid
Tue Mar 16 11:53:22 CET 2010


samb a écrit :
> Hi,
> 
> I've found a work around, inspired from Rob Williscroft :
> 
> class ReMatch(object):
>     """
>         Object to be called :
>         1st time : do a regexp.match and return the answer (args:
> regexp, line)
>         2nd time : return the previous result (args: prev)
>     """
>     def __call__(self, regexp='', line='', prev=False):
>         if prev:
>             return self.prev_match
>         self.prev_match = re.match(regexp, line)
>         return self.prev_match
> 
> re_match = ReMatch()
> 
> if re_match(r'define\s+(\S+)\s*{$', line):
>     m = re_match(prev=True)
>     # do some logic with m
> elif re_match(r'include\s+(\S+)$', line):
>     m = re_match(prev=True)
>     # do some logic with m
> else
>     # do some logic
> 
> Hope this is efficient ... I guess yes.

A direct attribute access is cheaper than a method call, and makes for a 
simpler API too:

class ReMatch(object):
      match = None

      def __call__(self, regexp, source):
          self.match = re.match(regexp, source)
          return self.match


re_match = ReMatch()

if re_match(r'define\s+(\S+)\s*{$', line):
      m = re_match.match
      # do some logic with m
elif re_match(r'include\s+(\S+)$', line):
       m = re_match.match
      # do some logic with m

My 2 cents...



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