Re: iterator sequences (was: Standard libraries)

[Mark Hamburg <mark@...>]

On Jan 1, 2010, at 7:42 AM, Wim Couwenberg wrote:

> function seq(f, state, key)
>    local function self(s, k, ...)
>        if type(s) == "function" then
>            f = s(self, f, k, ...) or f
>            return self, state, key
>        else
>            return f(s, k)
>        end
>    end
>    return self, state, key
> end

Could this be rewritten as:

	function seq( f, state, key )
		local function self( s, k, ... )
			if s == state then
				return f( s, k )
			else
				f = s( self, f, k, ... ) or f
				return self, state, key
			end
		end
		return self, state, key
	end

The assumption here being that the state isn't going to be used as a modification operator for the sequence. Is that more or less of a potential problem than the assumption that the state won't be a function?

The explicit iterate change I proposed would also potentially apply but I left it out for clarity.

Mark