On 4/19/07, Jose Luis Hidalgo <joseluis.hidalgo@gmail.com> wrote:
I'm not sure if is there any reason, but maybe this can help you, it
is a replacement of pairs written in pure lua.
do
local _pairs = pairs
function pairs (value)
if type(value) == "userdata" then
local g = getmetatable(value)
return g.__pairs(value)
else
return _pairs(value) -- original
end
end
end
Actually there's no reason to limit it to userdata. Whatever datum with a __pairs metamethod should let you override the behavior:
[...]
local mt = getmetatble(value)
return mt and mt.__pairs and mt.__pairs(value) or _pairs(value)
[...]
(Notice that the overhead happens outside of the for loop which typically uses pairs)
As for # not being overridable on tables, I never realized it, but that's quite puzzling. The worst part is, I don't think this can be fixed without touching the VM (except through a metalua macro of course :))
