I'd use something like (untested): 
opendir my $dh => $dir or die;
my %files;
   @files {map {lc} readdir} = ();    
closedir $dir;
my @missing = grep {/^(.*)\.did$/s && !exists $files {"$1.mrg"} keys %
+files;

[download]

Abigail

In reply to Re: Finding un-paired files in a directory by Abigail-II
in thread Finding un-paired files in a directory by inman

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