bug#7840: SYMBOL_VALUE in terminal.c (was 23.2.91; default-terminal-coding-system not inherited by created terminals)

[Stefan Monnier]

> I also don't understand the "internal function" argument: it sounds
> TRT to have a function that just fetches a symbol's value, without
> signaling an error if it is unbound.  Fsymbol_value, as it is now, is
> clearly coded for interactive use, which this isn't.

You mean "Lisp use" rather than "interactive", right?

> In any case, if you want people to avoid these APIs, please explain
> more why you dislike them, because so far it is utterly unclear, at
> least to me.

Basically Emacs variables provide
get/set/letbind/unbind/boundp/make-local/makunbound and everything else
is internal.  Any code which is not directly related to implementing
that functionality should go through those entry points, IMO.

find_symbol_value is the least harmful of the internal functions,
indeed, but it still requires extra care from the caller since it can
return Qunbound which is a value which should never escape to Lisp code.


        Stefan