Hi tilly,

My requirement is exactly what the attached program behaves like - only thing I did not want to use in my program was eval.

In the end, unfortunately, eval seems the only way out. I did not want it to be (I pointed out in the very beginning that eval would work but was not preferred).

Maintainance would be an issue, but then this approach would do away with people grepping through the source and locate the replacement expressions .. how useful is that too from the maintainance point of view?

With the horrific approach below, you can very well put the replacement string in an external config file and keep such things separate from the main program... in my view that is more maintainable... would you (or anyone else) not agree?

Why would anyone keep configurable things embedded in the logic/source code? 

use strict;
use warnings;

use Data::Dumper;

use Tie::File;

# open the file if it exists, but fail if it does not exist
use Fcntl 'O_RDWR';

our @array = ();

our $file = 'hai';

tie @array, 'Tie::File', $file, mode => O_RDWR or die $!;

our $SearchString = 'HAI WORLD Times ([0-9]+).*$';
our $ReplaceString = '"\t\t<exML LOLZ = \"" . unpack(\'a1\', $1) . "\"
+/>"';

my $elementIdx = 0;

while($elementIdx <= $#array)
{
    if($array[$elementIdx] =~ $SearchString)
    {
        # Maintain only the first character
        
        $array[$elementIdx++] = eval $ReplaceString;
    }
    else
    {
        splice @array, $elementIdx, 1;
        # we don't want this in the output
    }
}

untie @array;    # all done!

[download]

In reply to Re^4: Function call in regex replacement string by PoorLuzer
in thread Function call in regex replacement string by PoorLuzer

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