Hello Monks!

This question is all about keeping the written code as clean, clear and simple as possible.

Please consider the following piece of code (irrelevant parts are replaced by [...]):

[...]
    if ($text =~ /FATAL: Error while copying /) {
        my $dt = substr($text,0,20);
        my $me = index($text,' from ');
        my $ml = $me - 47;
        my $msg = substr($text,47,$ml);
        $me += 6;
        my $se = index($text,' to ');
        my $sl = $se - $me;
        my $source = substr($text,$me,$sl);
        my $sbs = $me + 2;
        my $sbl = $se - $sbs;
        my $sourcebis = q{\\\\ENCNRW0010}.substr($text,$sbs,$sbl);
        $se += 4;
        my $de = index($text,', error was:');
        my $dl = $de - $se;
        my $destination = substr($text,$se,$dl);
        File::Copy::copy $source.$msg,$destination;
        push (@mail,$dt.$msg.' from '.$sourcebis.' to '.$destination."
+\n");
        $text =~ s/FATAL: Error while copying /FATAL (Fixed): Error wh
+ile copying /g;
        print $text."\n";
    }
[...]

[download]

2 example lines of what $text could be:

2017-11-16 11:42:20 FATAL: Error while copying MX000017105279_2448299.
+1523788.IN.EDI from D:\EnecoEDIELArchive\B2B_ELEK\ to \\ENCNRW0012\En
+ecoData\EDIEL_IN\B2B_ELEK\, error was:
2017-11-16 11:42:21 FATAL: Error while copying MX000017105328_3626588.
+1523787.IN.EDI from D:\EnecoEDIELArchive\B2B_ELEK\ to \\ENCNRW0012\En
+ecoData\EDIEL_IN\B2B_ELEK\, error was:

[download]

So, with my code I need to extract several strings from $text. In case of the first example: 2017-11-16 11:42:20, MX000017105279_2448299.1523788.IN.EDI, D:\EnecoEDIELArchive\B2B_ELEK\ and \\ENCNRW0012\EnecoData\EDIEL_IN\B2B_ELEK\. Every other string found there is a constant by the way, which is why I can use those in my index().

Problem is these strings can be pretty much anything with any number of characters (apart from the datetime of course), the only way I know how to safely extract them is shown in the code snippet. I don't know about you but if I would see this in a code written by someone else, my head would start spinning.

The code works, so I would not classify this as a 'problem', but if for example next year something changes about the way the inputfiles are written, I will be having a hard time deciphering what I did here again. So I was just wondering if there is a clearer way of doing what I do here?

Maybe something like my $msg = "the string that comes between" 'copying ' "and" ' from ';? Is there a function that does what the double-quoted text says?

Thank you in advance!

In reply to Alternatives for index() ... substr() ? by zarath

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