Hi Monks

Can I use a return statement, leaving the regex and a sub, within a regex, like in the following example ? Or should this not be done because of any side effect ? (like loosing memory ...)

I do not see any side effect, but I have not looked intensivly.

(Remark: in my program, the sub convert is doing much more and the hash %def has many different strings as keys and vals)

Many thanks for your opinion !

use strict;
use warnings;

my %defs=(map {$_ => '-'}'a'..'p'); # generate simple example pairs
my $test1='a1 $a $q $c 2b';         # use undefined hash. => ERROR
my $test2='a1 $a $b $c 2b';         # only defined hashes => no ERROR

print '<'.convert($test1).">\n";
print '<'.convert($test2).">\n";

sub convert
{ $_=shift;
  s/\$([\w_\d]+)/unless(defined($defs{$1}))  
                 { print "ERROR: <\$$1> is not defined in ";
                   return($_);            # ok or bad style ??
                 } 
                 $defs{$1}
                /egx;
  return($_);
}

[download]
program output: 
ERROR: <$q> is not defined in <a1 $a $q $c 2b>
<a1 - - - 2b>

[download]

In reply to use return in regex => allowed or side effects ? by Anonymous Monk

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