Fix various issues and cleanup whitespace

[catwell]

No description provided.

[ajacksified]

This should say that it returns 1 rather than the expected 3.

[catwell]

With a given Lua implementation. But the definition in the language is even worse. In Lua 5.1:

any integer index n such that t[n] is not nil and t[n+1] is nil

So it could be 1 or 3.

In Lua 5.2 it is even clearer:

Unless a __len metamethod is given, the length of a table t is only defined if the table is a sequence, that is, the set of its positive numeric keys is equal to {1..n} for some integer n

So the operator could return anything. Or crash your program, for that matter. Actually I expect some later Lua implementations to raise an error in that situation.

Anyway, my point is: you cannot rely on it being 3 but you cannot rely on it being 1 either.

EDIT: If you think this undefined stuff is theoretical, guess what this prints:

print(#{1, 2, nil, 3})

[ajacksified]

That's true; maybe expand it as result depends on Lua implementation, then?

I admit, I only tested it in Lua 5.1.5 and Luajit 2.0.2 to confirm.

[catwell]

Yes, it depends on the implementation. And it is not consistent even on Lua 5.1.5. As I said in my edit above, if you put the hole just one step further it doesn't give the same answer:

Lua 5.1.5  Copyright (C) 1994-2012 Lua.org, PUC-Rio
> list = {}
> list[1] = "item"
> list[2] = "item"
> list[3] = nil
> list[4] = "item"
> =#list
4

If you are interested in the "why" see the implementation. Hint: binary search.

[ajacksified]

Thanks for the cleanup! Just the one note above.

[ghost]

It was very nice of catwell to provide a pull request with the applied fixes and I can not understand the hold up here. The return value of the length operator on a table which is not a sequence, and in the case of 5.2 does not have a __len metamethod, is not defined.

[ajacksified]

@aDevilInMe No hold up, I just have been very busy and haven't had a chance to merge. Will do so, after I fix the merge conflict, once I have time.