Re: String indexing again

[Michal Kottman <k0mpjut0r@...>]

On Mon, 2010-12-20 at 14:03 +0100, Axel Kittenberger wrote:
> > s[3] is being used to mean the 3rd character of s.
> 
> Not?

It is used in the manual to denote the 3rd byte in the string. It does
not work in Lua like that. Strings have their metatable __index pointed
to the 'string' table, imagine like the following was done when
initializing Lua:

setmetatable("", {__index=string})

Therefore, indexing a string doesn't result in an error, like it did in
previous versions. You can type s[3] in Lua, but it will always return
nil, because there is no such entry in the 'string' table. For example:

n = 1
print(n[1])
-- stdin:1: attempt to index global 'n' (a number value)

s = "1"
print(s[1])
-- nil, because strings have a metatable __index pointing to the string
table, and string[1] is nil