Python's regular expression?

[Duncan Booth]

Mirco Wahab wrote:

> If you wouldn't need dictionary lookup and
> get away with associated categories, all
> you'd have to do would be this:
> 
>    $PATTERN = qr/
>        (blue |white |red    )(?{'Colour'})
>   |   (socks|tights        )(?{'Garment'})
>   |   (boot |shoe  |trainer)(?{'Footwear'})
>    /x;
> 
>    $t = 'blue socks and red shoes';
>    print "$^R: $^N\n" while( $t=~/$PATTERN/g );
> 
> What's the point of all that? IMHO, Python's
> Regex support is quite good and useful, but
> won't give you an edge over Perl's in the end.

If you are desperate to collapse the code down to a single print statement 
you can do that easily in Python as well:

>>> PATTERN = '''
      (?P<Colour>blue |white |red)
  |   (?P<Garment>socks|tights)
  |   (?P<Footwear>boot |shoe  |trainer)
  '''
>>> t = 'blue socks and red shoes'
>>> print '\n'.join("%s:%s" % (match.lastgroup,
    match.group(match.lastgroup))
    for match in re.finditer(PATTERN, t, re.VERBOSE))
Colour:blue
Garment:socks
Colour:red
Footwear:shoe