you can make a shell/batch wrapper and invoke the script as perlRunAndShowSrc foo.pl...

/usr/bin/perl $@
cat $1
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Or, here's another way. First, define a module:

package foo;
use Filter::Simple;
FILTER {
  $_ .= "\n;print qq{\n===SOURCE CODE===\n$_};";
};
1;
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Then put that in your code:

use foo;
use strict;
use warnings;
print "hello world";
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i think i might toss this into an Acme module later today, assuming there isn't one already..