Set buffer-local variable in buffer other than the current one?

Question

I'm in buffer A and I want to set a buffer-local variable in buffer B. I'm currently doing:

(with-current-buffer B
  (setq-local some-var 'some-val))

but is there a way to do this without changing the current buffer, i.e. can I explicitly specify the buffer whose value I want to change?

Answer 1

What you're doing is correct.

is there a way to do this without changing the current buffer, i.e. can I explicitly specify the buffer whose value I want to change?

While there is nothing built in, you can trivially write a macro which takes all three arguments, and then does exactly what you were doing.

Answer 2

is there a way to do this without changing the current buffer

No, but buffer-local-value is a Generalized Variable, so you can use setf to take care of the buffer switching for you:

(setf (buffer-local-value 'some-var B) 'some-val)

This macroexpands to essentially the same code as what your wrote above:

(let* ((#1=#:v B))
  (with-current-buffer #1#
    (set (make-local-variable 'some-var) 'some-val)))