GNU bug report logs - #22147
Obsolete search-forward-lax-whitespace

Previous Next

Full log

View this message in rfc822 format

From: Artur Malabarba <bruce.connor.am <at> gmail.com>
To: Drew Adams <drew.adams <at> oracle.com>
Cc: 22147 <at> debbugs.gnu.org, Juri Linkov <juri <at> linkov.net>
Subject: bug#22147: Obsolete search-forward-lax-whitespace
Date: Thu, 17 Dec 2015 18:47:37 +0000

2015-12-17 17:21 GMT+00:00 Drew Adams <drew.adams <at> oracle.com>:
>>> char-fold-symmetric could wait for later, but we definitely need
>>> char-fold-ad-hoc now before the release because the users should be
>>> able to customize the default rules.
>>
>> Indeed.  Once we do that, we also need a variable to determine
>> whether we should derive the default table from the unicode
>> standard (like we currently do) or just use an empty default with
>> the ad-hoc rules slapped on top.
>
> Users should be able to define their own equivalence classes (groups),
> not just one class.  Each class should be the value of a user option.
>
> Here is one simple and flexible way to do this:
>
> 1. Define a user option, `char-folding-classes', which is a list of
>    any number of (OPTION-NAME DOC-STRING) pairs, where OPTION-NAME
>    is a symbol that will name a user option and DOC-STRING is its doc
>    string.
>
>    Each symbol would automatically be used to define an option (a
>    defcustom) that the user can then use to define a given equivalence
>    class.
>
> 2. The generated defcustom for each user option specified in option
>    `char-folding-classes' would allow for any number of entries, each
>    of which could be a `choice' of either of these defcustom types:
>
>    a. An alist, such as used currently in my `char-fold-ad-hoc' option:
>       Each entry is a list of a char and the strings that fold into it.
>
>    b. A function that populates such an alist.

I appreciate you probably put quite a bit of thought into this, but
IMO this would be over-engineering.

I think we should define two simpole defcustoms that determine how the
character-fold-table is generated: character-fold-ad-hoc (an alist)
and character-fold-derive-from-unicode-decomposition (a boolean).
This should be immediately configurable by anyone, without requiring a
big initial investment.

Then we also make character-fold-table into a defvar, and document it
as a proper exposed API, so advanced users can change it however they
want with hooks and local vars to however many different
values/equiv-classes they want.

This would offer a dead-simple defcustom that covers most cases, while
still allowing the versatility of having multiple options for those
who need it.

Previous Next

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.