in reply to \g{-2} for inside (?{ ... })

   m{
      (?(DEFINE)
         (?<x>
            ( . ) ( . )
            (?{ '...' })
         )
         (?<y>
            (?<y1> . ) (?<y2> . )
            (?{ print("($+{y1},$+{y2})") })
         )
         (?<z>
            ( . ) ( . )
            (?{ '...' })
         )
      )

      (?&y)+
   }x;

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Re^2: \g{-2} for inside (?{ ... })
by ikegami (Patriarch) on Nov 06, 2008 at 20:49 UTC
    Thanks. That's the only documented approach I've found that doesn't rely on counting captures, but it makes for mighty long patterns and mighty long names.
[reply]
      and mighty long names

      Can't you just use 'x' and 'y' over and over? Doesn't %+ give you the most-recently matched instance matching the given name?

      - tye        

[reply]
[d/l]

        Indeed! I misunderstood the documentation. 

        use 5.010;  # re features
use strict;
use warnings;

for ('abcdef') {
   m{
      (?(DEFINE)
         (?<x>
            (?<i1> . ) (?<i2> . )
            (?{ '...' })
         )
         (?<y>
            (?<i1> . ) (?<i2> . )
            (?{ print("($+{i1},$+{i2})") })
         )
         (?<z>
            (?<i1> . ) (?<i2> . )
            (?{ '...' })
         )
      )

      (?&y)+
   }x;
}

print("\n");

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[reply]
[d/l]

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