Re: Global by default

[David Olofson <david@...>]

On Tue, Feb 12, 2013 at 7:30 PM, Dirk Laurie <dirk.laurie@gmail.com> wrote:

2013/2/12 Peter Slížik <peter.slizik@gmail.com>:

> Okay, here's the new thread I announced a while ago...
>
> Lua-users wiki cites Roberto's words:
>
> "Local by default is wrong. Maybe global by default is also wrong, [but] the
> solution is not local by default."
>
> Could anybody who understands Lua innards elaborate?
>

One possible reason might be that Lua only allows so many
local variables, 200 I think, the number must fit into one byte
otherwise the whole VM needs to be redesigned. Whereas
the number of global variables is for all practical purposes
unlimited.

IIRC, local variables are implemented over VM registers (similar to how a native language uses CPU registers and/or the stack), so the limit would be per-function. Not a problem normally, that is.

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