I didn't think the OPed code was really so terrible to begin with (once the  $plsname =~ s/\//_/g; statement is fixed). But in an attempt to "one-liner-ize" the code, and building on BrowserUk's post (and using my preferred regex practices), here's this: 

c:\@Work\Perl\monks>perl -wMstrict -le
"my $curdir   = 'Y:\Music\Schubert\Lieder\Terfel';
 my $startdir = 'Y:\mUsIc';
 ;;
 my $plsname = $curdir;
 $plsname =~ s{ \A (?i) \Q$startdir\E \\ (.+) \z }
              { (my $r = $1) =~ tr{\\}{_};  $r . '.pls'; }xmse;
 print qq{'$plsname'};
"
'Schubert_Lieder_Terfel.pls'

[download]
And is that really any better? Again, your call.

If you have Perl version 5.14+, it's possible to slightly simplify the  s/// replacement executable code above to
    $1 =~ tr{\\}{_}r . '.pls';
and in fact you could go all the way to 

c:\@Work\Perl\monks>perl -wMstrict -le
"my $curdir   = 'Y:\Music\Schubert\Lieder\Terfel';
 my $startdir = 'Y:\mUsIc';
 ;;
 my $plsname =
   $curdir =~ s{ \A (?i) \Q$startdir\E \\? }{}xmsr =~ tr{\\}{_}r . '.p
+ls';
 print qq{'$plsname'};
"
'Schubert_Lieder_Terfel.pls'

[download]
I hope this hasn't gone too "all PerlMonks" on you, and includes at least a hint (update: but not a single drop!) of Socrates.

Update: For info on the  /r modifier added in Perl version 5.14, see  s/// in Regexp Quote-Like Operators and  tr/// in Quote-Like Operators, both in perlop.

Give a man a fish:  <%-{-{-{-<

In reply to Re: Combining regexes by AnomalousMonk
in thread Combining regexes by davies

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