bug#56682: Fix the long lines font locking related slowdowns

[Stefan Monnier]

>>>>> There have been many more complaints about being unable to edit a file
>>>>> with a 5000+ line comfortably, than about editing 100+ MB files.
>>>> Also because we have things like so-long to handle the large file case.
>>> These things are expedients for want of anything better, aren't they?
>> Yes, just like the narrowing your use in your long lines patch.
> That's... unfair.

I disagree.  And I don't think it's something you should be ashamed of:
it's standard practice to use expedient solutions for want of anything
better.  It's how we make progress.

Those expedient solutions (i.e. those cheap solutions that still cover
most cases tolerably) might be "not ideal" but finding them is usually
not easy, so pride would be more appropriate.

>> They're slightly different in that they don't try to prevent replacing
>> those solutions with something better (or worse), tho.
> When one looks at things from far enough, everything is indeed "slightly
> different" from everything else.  For example, the Statue of Liberty is
> "slightly different" from Empire State Building.

I agree with you that "slightly different" is a euphemism when
describing whether an expedient solution can be overridden or not.
:-)


        Stefan