RE: [External] : Re: Use regex in ~/.emacs.d/init.el to match no_proxy.

[Drew Adams]

> … and that is also the huge advantage of not having only hu-
> man-readable strings in Emacs's init file, but being able to
> program in Emacs Lisp whatever is needed.  For "simple" cus-
> tomizations, I recommend the Customization interface: It al-
> lows to enter complex data structures in a guided way and
> does The Right Thing™.

+1.  Like many (most?), I find the Customize UI
somewhat ugly and clunky.  And it's hard to ask
it what functions are involved underneath etc.
(hard to "ask Emacs" there).

But it is relatively straightforward.  And it
do things correctly (setting, saving, backing
up, etc.; I don't mean that the UI is great).

And this is true not only for setting "simple"
option values etc.  If the person writing the
defcustom (option definition) makes the effort,
the type-checking can be quite refined.

Unfortunately, too often, I think, defcustom
:type definitions are made too hastily or too
lazily.  Partly it's a case of there being a
lack of predefined types for some things,
coupled with lack of knowledge (or inherent
difficulty) of defining new types. 

But pretty much any Lisp values can be nailed
down relatively tightly, using `restricted-sexp'.
See (elisp) `Composite Types':

https://www.gnu.org/software/emacs/manual/html_node/elisp/Composite-Types.html

But Customize (and its underlying functions)
doesn't really help with some kinds of Emacs
customization - fiddling with the mode-line,
font-lock, menus, etc.  For that, we could use
not only better UI for users to change things
but even better/handier Elisp knobs.