Comparing against the single-quote symbol '

Comparing against the single-quote symbol '

[Nordlöw]

How do I explicitly compare against the single-quote symbol ' in emacs
lisp programs?

I thought I could use this expression
  (equal prefix \')

where the value the symbol `prefix' is
  \'

but \' is not allowed in lisp-code; it complains about void variable
\'

I also get extraordinary annoyed about the behaviour of (accidentally)
evaluating
  '(
It automatically hides the rest of the buffer and remembers this state
when I open it again. I think it has something to do with buffer
visibility.


Thanks in advance,
Nordlöw

Re: Comparing against the single-quote symbol '

[David Kastrup]

Nordlöw <per.nordlow@gmail.com> writes:

> How do I explicitly compare against the single-quote symbol ' in emacs
> lisp programs?
>
> I thought I could use this expression
>   (equal prefix \')
>
> where the value the symbol `prefix' is
>   \'
>
> but \' is not allowed in lisp-code;

Since when?

> it complains about void variable \'

Sure.  The symbol \' has no variable value by default.  If you don't
want to access its variable value but rather its symbol, you need to
quote it.  And sure enough
'\'
works just fine (even though it looks misleadingly symmetric).

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum

Re: Comparing against the single-quote symbol '

[djfiander]

On Jun 10, 1:07 pm, David Kastrup <d...@gnu.org> wrote:
>
> Sure.  The symbol \' has no variable value by default.  If you don't
> want to access its variable value but rather its symbol, you need to
> quote it.  And sure enough
> '\'
> works just fine (even though it looks misleadingly symmetric).

Of course, if you want to see if the variable 'prefix' contains the a
single quote character, then you probably want to say

    (equal prefix ?')

- David

Re: Comparing against the single-quote symbol '

[Nordlöw]

On 10 Juni, 19:25, djfiander <da...@fiander.info> wrote:
> On Jun 10, 1:07 pm, David Kastrup <d...@gnu.org> wrote:
>
>
>
> > Sure.  The symbol \' has no variable value by default.  If you don't
> > want to access its variable value but rather its symbol, you need to
> > quote it.  And sure enough
> > '\'
> > works just fine (even though it looks misleadingly symmetric).

Superb!, '\' works for me!

Thanks,
Nordlöw

Re: Comparing against the single-quote symbol '

[Nikolaj Schumacher]

Nordlöw <per.nordlow@gmail.com> wrote:

> I also get extraordinary annoyed about the behaviour of (accidentally)
> evaluating
>   '(
> It automatically hides the rest of the buffer and remembers this state
> when I open it again. I think it has something to do with buffer
> visibility.

Does M-x top-level help?

regards,
Nikolaj Schumacher