Canonical way of marking a buf local var to be safe if nil/t?

Canonical way of marking a buf local var to be safe if nil/t?

[Kaushal Modi]

Hi,

What would be a canonical way (if any) of setting a var to be a safe buffer
local variable as long as its value is either nil or t?

I use

(put 'my-foo-var 'safe-local-variable (lambda (val) (or (equal val nil)
(equal val t))))
-- 

-- 
Kaushal Modi

Re: Canonical way of marking a buf local var to be safe if nil/t?

[John Mastro]

Kaushal Modi <kaushal.modi@gmail.com> wrote:

> What would be a canonical way (if any) of setting a var to be a safe buffer
> local variable as long as its value is either nil or t?
>
> I use
>
> (put 'my-foo-var 'safe-local-variable (lambda (val) (or (equal val nil)
> (equal val t))))

Use `booleanp':

booleanp is a compiled Lisp function in ‘subr.el’.

(booleanp OBJECT)

Return t if OBJECT is one of the two canonical boolean values: t or nil.
Otherwise, return nil.

-- 
john

Re: Canonical way of marking a buf local var to be safe if nil/t?

[Kaushal Modi]

On Thu, May 12, 2016 at 1:39 PM John Mastro <john.b.mastro@gmail.com> wrote:

> Use `booleanp':
>
> booleanp is a compiled Lisp function in ‘subr.el’.
>
> (booleanp OBJECT)
>
> Return t if OBJECT is one of the two canonical boolean values: t or nil.
> Otherwise, return nil.
>

Thanks! I had a gut feeling that something basic like this had to be
already covered :)
-- 

-- 
Kaushal Modi