Re: Understanding the "let" construct and the setting of variables

[Emanuel Berg]

steve-humphreys wrote:

> This gets me to "defvar". I have read that "setq" does net
> actually make a variable. It is defvar that makes a variable
> available. When reading the "Intro to Emacs Lisp", the focus
> is on using "setq".

`setq' is enough, it does the real job alright, but the
byte-compiler will complain if there isn't a `defvar'
before it.

Also with defvar you can set a default value and add
a docstring. None of that is mandatory and the default value
can even be confusing IMO.

Just think of defvar as a way of telling Emacs and everyone
else, "I intend to use a variable with this name."

This is enough, and always do it (_at least_ do that, of
course by all means set the default and add a docstring if
that fancies you), but always and at least do this:

(defvar some-var)
(setq   some-var some-value)

That's enough. You have what you need and the byte-compiler
doesn't complain.

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