Another possible optimization: 
m{
  A
  (?: [^AB]+ | .B )*
  [^AB]*
  A
}x;

[download]


$_="goto+F.print+chop;\n=yhpaj";F1:eval

In reply to Re: Perl's regex engine causes me distress by japhy
in thread Perl's regex engine causes me distress by japhy

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