It depends a lot on your situation.

If you need to support Perl older than 5.10, then named captures are out. Full stop.

If you're in a tight loop, using positional variables, or assigning the result of the regexp match to a list of variables, will be faster than named captures which use a tied hash.

In the case where you're passing around regexps as part of an API, then named captures seem the best idea. For example, you have a function which accepts a filehandle and a regexp, and does some processing on the file, using the regexp to extract the right data.

sub process_file {
   my ($fh, $re) = @_;
   while (<$fh>) {
      next unless /$re/;
      # do stuff with captured data
   }
}

[download]

Here named captures make a lot more sense because they give the caller a lot more flexibility. If you have something like:

my $account_number = $1;
my $deposit_amount = $2;

[download]

... then it ties the input format so that the deposit amount can never be in the first column, before the account number. Named captures don't suffer from that.

toby döt ink

In reply to Re: Named captures or positional variables by tobyink
in thread Named captures or positional variables by MidLifeXis

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