Re: [PATCH v2 4/5] Make boundary characters for --color-words configurable

From: Jakub Narebski <jnareb@gmail.com>
Date: May 12, 2008, 19:57 UTC
Message-ID: <200805122157.57366.jnareb@gmail.com>
In-Reply-To: <7vve1jxrg9.fsf@gitster.siamese.dyndns.org>

Junio C Hamano wrote:

Show 20 quoted lines

> Jakub Narebski <jnareb@gmail.com> writes:
>> "Ping Yin" <pkufranky@gmail.com> writes:
>>>
>>> To achieve the best, we have to find the pairs of lines (one minus and
>>> one plus for each pair) which most match each other, and then do the
>>> word diff for each pair.
>>
>> Wouldn't be enough to treat run of plus/minus lines as a single block,
>> tokenize, do token-based (as opposed to line-based) diff, then show it
>> using linebreaks of the destination file (pluses line)?
> 
> I tried the "using linebreaks" but I discarded it because I did not think
> it would work.  If we rewrite the last three lines above with this single
> line:
> 
>> Wouldn't be enough to use magic?
> 
> and apply that algorithm between the two, then we would get a long single
> line that has words painted in red, two lines worth, followed by green "to
> use magic?"  and finally an end-of-line.

It looks then like inserting (retaining?) newlines in word/token based --color-words output isn't simple. It would have to produce readable output both for the case you stated/mentioned, and for the opposite case (replacing single line by multiple lines). What's even more difficult, it should produce clear output for a simple case of rewrapping output, e.g. the following as replacement.

>> Wouldn't be enough to treat run of plus/minus lines as a single
>> block, tokenize, do token-based (as opposed to line-based) diff,
>> then show it using linebreaks of the destination file (pluses
>> line)?

Gaahh... I don't think this (word diff/token diff) is something computer science has worked on?

-- 
Jakub Narebski
Poland