Jean-Michel Pichavant
3/16/2010 10:56:00 AM
samb wrote:
> 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.
>
> Cheers,
> Sam
What do you mean by efficient ? If you're talking about speed, make sure
you care about it before doing some optimization.
If you talk about readability then it is absolutely *not* efficient (to
my humble opinion).
define, include = re.match(r'define\s+(\S+)\s*{$', line),
re.match(r'include\s+(\S+)$', line)
if define:
# do some stuff
elif include:
# do some other stuff
else:
# hello world
If you then have some speed problem with that script, you'll start
caring about how to execute if faster by making sure that only necessary
calls to re.match are done.
match = re.match(r'(define)\s+(\S+)\s*{$', line) or
re.match(r'(include)\s+(\S+)$', line) # note that the second operand is
executed only if the first is None
if match.group(1) == 'define':
# do some stuff with match.group(2)
elif match.group(1) == 'include':
# do some other stuff with match.group(2)
else:
# hello world
JM