From: daz <dooby@...10.karoo.co.uk>
Date: 2005-07-31T10:41:03+09:00
Subject: Re: Which Regex-Engine will be used in Ruby 1.8.3 Release?


Yukihiro Matsumoto <matz@ruby-lang...> wrote:
>
> Christian Neukirchen writes:
> > |Will there be a 1.8.x release with Oniguruma being the default engine?
>
> It's not planned, for compatibility's sake.  Any opinion?
>

Compatibility in the sense that an invalid Regexp for the current engine
could be interpreted as something exotic by Oniguruma ?


Would something like the following be possible? :

1.8.3 (say, from Dec 2005) include _both_ (i.e. selectable)

  Regexp::service_level(0) (DEFAULT) - Current engine
  Regexp::service_level(1)           - Oniguruma ( strict emulation of level(0) )**
  Regexp::service_level(2)           - Oniguruma ( full )

.... where service_level(n) calls Init_Regexp_n()
(The transitional method name would *not* become part of the language.)

1.8.4 (or after 6 / 12 months)

  Regexp::service_level(0)           - Current engine ( in case of emergency ;)
  Regexp::service_level(1) (DEFAULT) - Oniguruma ( strict emulation of level(0) )**
  Regexp::service_level(2)           - Oniguruma ( full )

1.8.5 (?)

  Regexp::service_level(1)           - Oniguruma ( strict emulation of level(0) )**
  Regexp::service_level(2) (DEFAULT) - Oniguruma ( full )


A big advantage would be to enable behavioural comparisons
from a script without switching between 1.8 / 1.9 ?

Quite conservative, too.  No-one needs to be concerned that it's there.

** If I read correctly, the Oniguruma team have allowed for
   building versions tailored to a variety of users.

   Actually, I'm still going to post but the difference between
   level(1) & (2) would require adding a lot of almost duplicate
   code to the Ruby distribution _or_ an awful lot of added logic
   which I wouldn't wish on anyone.

   Some clever folks out there though :-)


daz