Re: master e315544: ; * src/fileio.c (Fdirectory_append): Doc fix.

[Michael Albinus]

Lars Ingebrigtsen <larsi@gnus.org> writes:

Hi Lars,

>>> This should probably emphasize the fact that it ignores file name
>>> handlers.
>>
>> The NEWS entry specifically, or the docstring and/or info entry?
>
> I'm not entirely confident that it'll keep ignoring file name handlers,
> so the less said the better.

If you want file-name-concat being well optimized, you shall not use
file name handlers:

--8<---------------cut here---------------start------------->8---
(benchmark
 1000
 (let (file-name-handlers)
   (concat (file-name-as-directory "/tmp") "foo")))
=> "Elapsed time: -0.000004s"

(benchmark
 1000
 (let nil
   (concat (file-name-as-directory "/tmp") "foo")))
=> "Elapsed time: 0.000049s"
--8<---------------cut here---------------end--------------->8---

It's not heavy in terms of absolute time, but still a factor of 10.

Best regards, Michael.