Re: Metatables index

[Jonathan Goble <jcgoble3@...>]

On Sun, Nov 8, 2015 at 6:12 PM, Andrew Starks <andrew.starks@trms.com> wrote:
> You need a metatable with the __index metamethod defined. If
> you set that field to a table, then Lua will look at that table as a
> back up, such that these two lines of Lua will do the same thing:
>
> ```
> x = setmetatable({}, {
>     __index = table
> })
>
> x = setmetatable({}, {
>     __index = function(self, i)
>         return rawget(table, i)
>     end
> })
> ```
>
> Notice that in the second example, i used rawget. Lua does rawget when
> you use the first method. This was a design choice and the reverse can
> be done by just replacing the return line with `return table[i]`.

Nope. From the 5.3 manual: [1]

"If it is a table, the final result is the result of indexing this
table with key. (This indexing is regular, not raw, and therefore can
trigger another metamethod.)"

[1] http://www.lua.org/manual/5.3/manual.html#2.4