Maybe it's a bug, maybe it's an obscure feature. Anyway, this is a fragile construct for border-checking of the flip-flop operator as it will be broken by a regex match within the if-block.

The required information for such a check is provided by the flip-flop operator itself: it returns the current "loop number", with "E0" appended to the final loop call.

Here is a more robust version: 

perl -le 'print for a .. h' | perl -nle 'if (my $ff = (/d/ .. /h/)) { 
+next unless $ff =~ /(?:^1|E0)$/; print }'

[download]

Greetings,
-jo

$gryYup$d0ylprbpriprrYpkJl2xyl~rzg??P~5lp2hyl0p$

In reply to Re: Empty pattern in regex by jo37
in thread Empty pattern in regex by choroba

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