Hmmm

> The fix doesn't work because the regex has to decide which non-greedy ? has "precedence".

strange, it works like I initially thought

  DB<63> print join "|",'abc' =~ /a(.+?)(c)?/
b|c
  DB<64> print join "|",'abd' =~ /a(.+?)(c)?/
b|

[download]

well you seem to have other issues I can't see.

EDIT

Interesting 

  DB<84> print join "|",'a<c1<c2' =~ /(.+?)<(c.)?/ # ok
a|c1

  DB<85> print join "|",'a<b1<b2' =~ /(.+?)<(c.)?/ # ok
a|

  DB<86> print join "|",'a<b1<c2' =~ /(.+?)<(c.)?/ # oops
a|

[download]

you might want to use use re 'debug' to parse whats happening.

update

ah now it's clearer

  DB<89> print join "|",'a<b1<c2' =~ /(.+?)(c.)?/
a|

[download]

The non-greedy is finishing as soon as it succeeds, and c. is optional

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re^4: Regex Optional capture doesn't (updated) by LanX
in thread Regex Optional capture doesn't by NetWallah

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