Mellow Funks,
My problem (no sniggering up the back there) , in this case is to build a regular expression to match and extract some significant digits from some strings, given a mask with a placeholder. For example.

numberedfiles.@.tif # mask with placeholder.
foreground.001.tif
foreground.002.tif # etc ad nauseum.

[download]
of course I am limiting myself for the moment to strings that are dot seperated, and to be honest the code I have works nicely, and allows me to extract the significant digits, but how might I apply this to include a placeholder for extention (in this case image-format) - it becomes more tricky. I am posting what has dribbled out my ears today in the hope that some of you lateral thinkers can widen the crack that floods my brain with light.


#!/usr/bin/perl -w
use strict;

my $mask = shift @ARGV;
my @segment = split /\./, $mask;
my @re = map {  my $r;
                if ($_ eq '@') { $r ='(\d+)' }
                else { $r= '\w+' }
                $r } @segment;

my $re ='^' .  join ('\.' , @re) . '$';
my $name = shift @ARGV;
my ($digits) = $name =~ /$re/;
print $re , $/;
print $digits, $/;

[download]
thanks.
I can't believe it's not psellchecked

In reply to Building regexp from a 'mask' string of placeholders. by submersible_toaster

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