Re^5: Empty pattern in regex

Of course, you are probably right, but why did this work?

  % perl -le 'print for a .. z' | perl  -nle 'if (/d/ .. /h/) { next unless "m//"; print }'
  d
  e
  f
  g
  h

Is that just interpolation at work? Do we have to read the source code to understand what is going on here, or is supposed to be going on? Talk about ambiguity... I tried //; m//; and "m//;" on that Foy code I reported and none yielded a successful match. Every example reported:

No nothing
$1: 
$2: 
$3: 
$&: Perl

the value from the previous successful match.

Comment on Re^5: Empty pattern in regex

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Re^6: Empty pattern in regex by choroba (Cardinal) on Oct 19, 2023 at 14:55 UTC
> but why did this work? `next unless 1;` never runs next, as 1 is always true. So is "m//" or any other non-empty string different to `0`. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]