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Comment by tantalor | Hacker News Reader

Not mentioned is the common idiom of assigning regexp matches.

In perl,

> my ($a, $b) = '12' =~ /(\d)(\d)/;

In python,

> (a, b) = re.match('(\d)(\d)', '12').groups()

Note the python code here will throw an AttributeError if the match fails, whereas the perl will just assign undef to the variables.

Alternatively, use named captures:

  > obj = re.match('(?P<id>\d\d)(?P<name>\w+)')  
  > id = obj.group('id')  
  > name = obj.group('name')

Nice!

Actually, perl will return an empty list, which if then evaluated in scalar context will return 0, which is boolean false. So

  if (my ($x, $y) = '12' =~ /(\d)(\d)/) {
    <use $x and $y here>
  }

is the normal idiom.