Re: Flush the term upvalue from 5.1 manual

[Boyko Bantchev <boykobb@...>]

On 11/22/05, Chris Marrin <chris@marrin.com> wrote:
> I think upvalue is a completely reasonable and clear term. Any
> terminology used will be obtuse to those new to the language. So it is
> better to have a short and easy-to-remember. I find "inherited binding
> reference" to be at least as obtuse as upvalue :-)

For the record, the only place except Lua that I find the word
`upvalue' in use is Mathematica, where there are `downvalues'
as well:
http://documents.wolfram.com/mathematica/book/section-2.5.10 .
However, Mathematica's use of `upvalue' is different.

The term `non-local variable' is a bit longer but often used in
other languages for what an upvalue is in Lua: a variable which
is neither local to a function being considered, nor global, i.e.
one that is local in an outer context.  Moreover, this use of
`non-local' is consistent with `non-local exits' in other languages
(and in a proposal of Rici Lake some time ago in this list).

That said, I am not advocating that Lua changes its preferred
terminology -- it is the right of Lua's authors and maintainers
to choose it. Were it, say, `green' in place of upvalue, I would
also be happy, provided a clear, unambiguous definition of
`green' is given :)