keypad-*-setup

[Drew Adams]

I think the doc for keypad-setup, keypad-shifted-setup, and
keypad-numlock-shifted-setup is pretty poor. Let me put it a different way:
I can't understand it.

The Emacs manual essentially sends you off to Customize for an
understanding, and Customize says only things that are incomprehensible to
me, such as "When selecting the plain numeric keypad setup, the character
returned by the decimal key must be specified." Specified how, where, what
for? What is "the character returned by the decimal key"? What is "the
decimal key"? (decimal point key perhaps? a decimal number key 0-9 perhaps?)
Quite a puzzle.

I suppose this is generally about having configurations of key bindings for
the keypad when it is shifted, Num Lock is depressed, both, and neither, but
that's all I've been able to gather from the doc.

One of the possible values is even "Unspecified/User-Defined", but I have no
idea how that works. And what is the difference between "Plain numeric
keypad" and "Numeric Keypad with Decimal Key"? Shouldn't the doc explain
what each of these values means?

Could someone savvy please improve this doc a bit?