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On 14 Jan 2010, at 22:51, Klaus Ripke wrote:
On Sat, Jan 09, 2010 at 12:52:33PM +0300, Alexander Gladysh wrote:
On Sat, Jan 9, 2010 at 12:37, steve donovan < > wrote:
2010/1/9 Ignacio Burgueño <>:
17. Documented behaviour of ipairs() is changed from "iterates until *first nil*" to "traverses table length elements as defined by length

This is more consistent, but given how strange #t is when t has a
number of holes, it isn't necessarily more useful.

(1) Don't have holes in tables you want to measure with #, that's all.

That's why this change to rely on #t is completely beyond me.

It might be intended for tables that redefine the meaning of #:

Lua 5.2.0 (work2)  Copyright (C) 1994-2010, PUC-Rio
> m={}
> m.__len = function() return 3 end
> m.__index = function(_, ...) return ... end
> t = setmetatable({}, m)
> for k,v in ipairs(t) do print(k,v) end
1	nil
2	nil
3	nil

As much as I love those metamethods tricks, I must say they seem to me more scary than useful when they do not come with their 'raw*' counterparts. I remember pretty well how it felt the few times all I wanted was a 'rawtostring', so I rather not think how it will feel nor the many times I might be hoping for a 'rawipairs' in the future. (or a 'rawlen' for that matter)

Renato Maia
Computer Scientist