inman has asked for the wisdom of the Perl Monks concerning the following question:

I am working with a directory that contains both data files and marker files. The marker files have the same base name as the data files but a different extension. They are used as markers that identify the data files that are no longer used. As a result, the files exist as pairs unless they are current in which case only the data file is present. An example directory listing would contain:

00000001.did 00000001.mrg 00000002.did 00000002.mrg 00000003.did

I want to work with all of the current data files so I am using the code below to find the list of data files that does not have a corresponding marker file.

sub unmergedFiles { my $dir = shift; my %merged; my @files; # create the hash containing the merged files foreach (glob ($dir."/*.mrg")) { if ( /(\S+)\.mrg/i ) { $merged{lc ($1 . ".did")} = "1"; } } foreach (glob ($dir."/*.did")) { unless (exists $merged{lc($_)}) { push @files, $_; } } # return style as per node 311537! return wantarray ? @files : \@files; }

This code works just fine but I would like the opinion of more learned monks as to how this code can be improved. A couple of things spring to mind:

All comments gratefully received!