buffer-name in find-file-hook

buffer-name in find-file-hook

[Joe Bloggs]

Hi, I am writing a function to add to find-file-hook for hiding text regions saved in 
a list. I need to know the buffer-name of the opened file, so that I can compare it
with the buffer names of the saved regions.
Here is the function:

;; hook for re-hiding regions when new file is opened
(defun hide-region-find-file-hook ()
  (dolist (current hide-region-overlays)
    (if (eq (buffer-name) (car current))
        etc...

the problem is that the 'if' statement never evaluates to true.
I tried debugging in edebug, and both (buffer-name) and (car current) 
evaluate to the same string, but for some reason the 'if' statement evaluates to 'nil'.
I have used the same construct in another function that is called from within the buffer, 
and it works fine.
Can anyone help?

Re: buffer-name in find-file-hook

[Joost Kremers]

Joe Bloggs wrote:
>     (if (eq (buffer-name) (car current))
> 
> the problem is that the 'if' statement never evaluates to true.
> I tried debugging in edebug, and both (buffer-name) and (car current) 
> evaluate to the same string, but for some reason the 'if' statement evaluates to 'nil'.

check out the section on equality predicates in the elisp manual:

(info "(elisp) Equality Predicates")


-- 
Joost Kremers                                      joostkremers@yahoo.com
Selbst in die Unterwelt dringt durch Spalten Licht
EN:SiS(9)

Re: buffer-name in find-file-hook

[Joe Bloggs]

Joost Kremers <joostkremers@yahoo.com> writes:


>
> check out the section on equality predicates in the elisp manual:
>
> (info "(elisp) Equality Predicates")
>
Just did, thanks. Changed 'eq' to 'equal' and it now works fine.
Should have checked before posting, but frustration got the better of me.

Re: buffer-name in find-file-hook

[Nikolaj Schumacher]

Joe Bloggs <who@cares.invalid> wrote:

> Hi, I am writing a function to add to find-file-hook for hiding text
> regions saved in a list. I need to know the buffer-name of the opened
> file, so that I can compare it with the buffer names of the saved
> regions.

Why are you using the buffer name?  Wouldn't it be better to use
something more unique, i.e. the file name?


regards,
Nikolaj Schumacher

Re: buffer-name in find-file-hook

[Joe Bloggs]

Nikolaj Schumacher <me@nschum.de> writes:

> Joe Bloggs <who@cares.invalid> wrote:
>
>> Hi, I am writing a function to add to find-file-hook for hiding text
>> regions saved in a list. I need to know the buffer-name of the opened
>> file, so that I can compare it with the buffer names of the saved
>> regions.
>
> Why are you using the buffer name?  Wouldn't it be better to use
> something more unique, i.e. the file name?
>
>
> regards,
> Nikolaj Schumacher

I figured that I may want to move the file, but still keep the hidden regions.

Re: buffer-name in find-file-hook

[Nikolaj Schumacher]

Joe Bloggs <who@cares.invalid> wrote:

> Nikolaj Schumacher <me@nschum.de> writes:
>
>> Joe Bloggs <who@cares.invalid> wrote:
>>
>>> Hi, I am writing a function to add to find-file-hook for hiding text
>>> regions saved in a list. I need to know the buffer-name of the opened
>>> file, so that I can compare it with the buffer names of the saved
>>> regions.
>>
>> Why are you using the buffer name?  Wouldn't it be better to use
>> something more unique, i.e. the file name?
>>
>>
>> regards,
>> Nikolaj Schumacher
>
> I figured that I may want to move the file, but still keep the hidden
> regions.

Unfortunately files of the same name (say "README") will then also share
the same hidden regions.  On the other hand, buffers can be renamed or
"uniquified" and lose settings.

Maybe you could generate a hash to catch renamed files.


regards,
Nikolaj Schumacher