Re: Question about 5.0 for loop

[Roberto Ierusalimschy <roberto@...>]

> But I don't see any way _s could ever be modified

It is not. Maybe the name "state" is misleading. Actually, there are two
"states": _s and `var1'. _s is fixed (e.g. the table or the file you are
traversing), while `var1' varies.

Notice that we start with

>          local _f, _s, var_1 = explist

so we do have a way to assign a value to _s. nexti(t), for instance,
returns a function *and* `t' ;-)

For several simple iterations such state is enough (e.g. traversing tables,
reading the lines of a file, etc.). For more complex ones, you can
either use a closure or put a table in _s (and as much state as you want
inside the table).

-- Roberto