doc for table.concat is slightly misleading

[David Jones <drj@...>]

The documentation for table.concat implies that table.concat{x,y,z}  
is equivalent to x .. y .. z, but this isn't so when metatables are  
involved:

> t = setmetatable({}, { __concat = function(x, y)return x.x .. y  
end })
> t.x='foo'
> print(t .. 1 .. 1)
foo11
> table.concat{t,1,1}
stdin:1: bad argument #1 to 'concat' (table contains non-strings)
stack traceback:
        [C]: in function 'concat'
        stdin:1: in main chunk
        [C]: ?

Personally, as someone who doesn't do much string manipulation in  
Lua, I'd be equally happy with either a doc change or a behaviour  
change.

drj