Simplify constant value determination

Tomte has asked for the wisdom of the Perl Monks concerning the following question:

Hi,
to allow for determination exactly which version of a program runs (and produces errors), I have the following statement to fetch the subversion revision-number in my code

use constant REVISION => eval {
    ( $_ = '$Id: mcdt.pl 2081 2006-08-25 16:16:27Z tomte $' ) =~
      s/\$Id: mcdt.pl (\d+) .*/$1/;
    $_;
};
[download]

While I think its reasonable and not too ugly, I wonder if theres a more concise/elegant way of retrieving the revision-number as a constant.

Edit: elimininated /g modifier

regards,
tomte

An intellectual is someone whose mind watches itself.
-- Albert Camus

Comment on Simplify constant value determination Select or Download Code

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Re: Simplify constant value determination by ysth (Canon) on Aug 25, 2006 at 16:37 UTC
Since you seem to just want the first group of digits: `use constant REVISION => ('$Id: mcdt.pl 2081 2006-08-25 16:16:27Z tomt +e $' =~ /(\d+)/g)[0];` [download] should do it. No need for eval or substitution here. Update: grr, I don't use g-less m// in list context often enough to remember what it returns. `use constant REVISION => '$Id: mcdt.pl 2081 2006-08-25 16:16:27Z tomte + $' =~ /(\d+)/;` [download]	[reply] [d/l] [select]
Re^2: Simplify constant value determination by Tomte (Priest) on Aug 25, 2006 at 16:52 UTC
the last one is what i was looking for - thanks and ++ysth - the wood for the trees etc. :) regards, tomte An intellectual is someone whose mind watches itself. -- Albert Camus	[reply]
Re: Simplify constant value determination by friedo (Prior) on Aug 25, 2006 at 16:36 UTC
How about: `use constant REVISION => q$Id: mcdt.pl 2081 2006-08-25 16:16:27Z tomte $ =~ /pl (\d+)/;` [download]	[reply] [d/l]

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