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On Tue, Nov 18, 2008 at 1:02 PM, Matthew Paul Del Buono <delbu9c1@erau.edu> wrote:
The closest you can do is use the __newindex metamethod. This isn't exactly what you've asked for, though you might be able to work it the way you want it to.

> t = {1,2,3}; setmetatable(t, {__newindex = function(t,k,v) print(t,k,v) rawset(t,k,v) end});
> t[5] = 4;
table: 000000000068BEC0 5       4
> t[5] = 5;
> t[3] = 2;

Take note that you only get __newindex called when it is new, by design. You can work around that by using __index as well, if you need to:

> t = setmetatable({}, {__index = {1,2,3}, __newindex = function(t,k,v)
>> print(t,k,v)
>> getmetatable(t).__index[k]=v;
>> end});
> t[5] = 4;
table: 000000000068BF60 5       4
> t[5] = 5;
table: 000000000068BF60 5       5
> t[3] = 2;
table: 000000000068BF60 3       2

But be careful with this as well, as you will lose the ability to use pairs() and ipairs() on the table without extra work.

Thanks this is a start, but how could I get pairs() and ipairs() to work again?
Thanks.
--
Regards,
Ryan