Feature #1201

Add relative group reference in back reference with nest level in regular expressions (e.g. \k<-5+1>)

Added by WoNaDo (Wolfgang Nádasi-Donner) almost 12 years ago. Updated almost 9 years ago.

Target version:


It should be possible to use relative group references in back reference with nest level.

Reason: As named in Ticket 1200 relative group references can be very helpful in writing subexpessions, which can be used later on as often as necessary in one regular expression.

Unfortunately back references with nest level, \k, \k, \k'n+level', and \k'n-level', do not allow relative group referencing, so they can only be used if one knows, how many normal groups are in the complete regular expression before the referenced group.

If there are relative group references possible, e.g. \k<-n+level>, \k<-n-level>, \k'-n+level', and \k'-n-level', these constructs can be used in subexpressions designed to be used more than once in a regular expression.

Related issues

Related to Ruby master - Feature #1200: Possibility for using named and normal groups together in regular expressionsRejected02/25/2009Actions

Updated by naruse (Yui NARUSE) over 11 years ago

This feature depends on oniguruma.


Updated by marcandre (Marc-Andre Lafortune) over 11 years ago

  • Assignee set to matz (Yukihiro Matsumoto)
  • Target version changed from 1.9.1 to 2.0.0




Updated by shyouhei (Shyouhei Urabe) over 10 years ago

  • Status changed from Open to Assigned



Updated by naruse (Yui NARUSE) almost 9 years ago

  • Status changed from Assigned to Closed

Ruby 1.9.1 supports this through Oniguruma 5.9.1.

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