Re: [PATCH] cc-mode: don't tread dir-local and file-local variables differently

[조성빈 <pcr910303@icloud.com>]

Michał Nazarewicz <mina86@mina86.com> 작성:

> To quickly recap, CC Mode treats ‘c-file-style’ differently depending on
> whether it comes from .dir-locals.el or a file-local variable.  For
> example, having the following in init.el:
>
>     (setq-default 'c-basic-offset 4)
>
> consider the following two scenarios:
>
> 1) /tmp/foo/.dir-locals.el exists and contains a single line:
>
>        ((nil . ((c-file-style . "bsd"))))
>
>    Opening an empty /tmp/foo/foo.c file results in ‘c-basic-offset’
>    being four and ‘c-file-style’ being "bsd".
>
> 2) /tmp/bar/.dir-locals.el does not exist but /tmp/bar/bar.c does and
>    contains a single line:
>
>        /* -*- c-file-style: "bsd" -*- */
>
>    Opening that file results in ‘c-basic-offset’ being eight and
>    ‘c-file-style’ being "bsd".  (Value of eight for the offset comes
>    from "bsd" style).
>
> I maintain that in both cases ‘c-basic-offset’ should be the same.
> I further maintain that its value should be eight.  Alan disagrees and
> maintains that cc-mode-hook should overwrite settings in dir-local
> variables but should be overwritten by settings in file-local variables.

As a user I think most people would expect the two results to be the same -  
the biggest use case of {dir,file}-local variables (at least known to me)  
is to maintain a consistent style between different Emacs customizations.

The person that added .dir-locals.el would have expected that all code  
inside this directory will follow the bsd-style — one should not have to  
consider various different customization scenarios and accommodate to them  
to have a consistent style.