Another debugging approach is to ask what all those strings look like when they're concatenated together inside the function. 

>perl -wMstrict -le
"my $regexStr = qr{[0-9]+};
 my $suff     = '.dn';
 my $getDir   = 'c:\sh\\';
 ;;
 my $concat = qq{$getDir$regexStr$suff};
 print qq{for debug: '$concat'};
"
for debug: 'c:\sh\(?^:[0-9]+).dn'

[download]

The first thing that catches the eye is that  (?^:[0-9]+) stuff in the middle of everything. What's that about? Clearly, it derives from the regex, but how does it relate to the specification of a path and file name? (Of course, one quickly realizes it is the stringization of the  Regexp regex object – not a string at all – that  qr// produces.)

Seeing the inappropriate nature of the data being fed to the Windoze  dir command is the first step toward thinking more clearly about what one ought to be doing.

In reply to Re: Passing regex to a subroutine by AnomalousMonk
in thread Passing regex to a subroutine by ll001

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