Re: Proposal: allow @, $, !, and ? in Lua identifiers

[steve donovan <steve.j.donovan@...>]

On Mon, Apr 28, 2014 at 10:59 AM, Dirk Laurie <dirk.laurie@gmail.com> wrote:
> We're in the Unicode/UTF8 era now. No reason why we can't have ≤,≥, ←and →
> for <=, >=, << and >> too. It's only a tiny patch to llex.c and if you ever need
> to send your program to someone else, it's trivial to translate.

Fair enough, but then we have the keyboard problem. In my editor
environment I've already got all the ctrl-<key> mappings assigned, →
is not going to be a single keystroke anyway.  There's a lot of muscle
memory involved in typing code, why mess with existing mental key
bindings?

An interesting presentation of the "why restrict ourselves" position
is here [1].  There is a pretty example of idiomatic Fortress code in
full flight, which is very readable if you are a mathematician.  (The
author also makes the point that regular expressions would have no
need for escapes if the basic elements of the grammar were some other
Unicode characters.)

However, the mechanics of coding (both embodied in our keyboards and
mental firmware) is an issue, when ease of writing is considered as
important of ease of reading.

I'm sympathetic with != being an alias for ~=, but once that becomes
official, it becomes a breaking change. 5.3 has the bitwise operators,
so it's a good time to talk about other breaking changes.

[1] "Problems of Symbol Congestion in Computer Languages"
http://xahlee.info/comp/comp_lang_unicode.html