Re: Shouldn't custom.el load wid-edit.el?

[Richard Stallman]

    What type does it record? See the example I gave (repeated below). defcustom
    _evaluates_ the :type sexp you give it.

Which is nearly always a constant.

     That means the defcustom needs to
    recognize the set of basic types at that time, in order to eval that sexp.

It just records the value.  It doesn't have to check it at all.

    > I did this, to let some code work also in older Emacs versions
    > that don't define type `color':
    >
    > (defcustom... :type (if (get 'color 'widget-type)
    >                         'color
    >                       'string)
    >  ...)

That is a very strange thing to do.  If it works, ok.
If it doesn't, that isn't a bug.