Re: ... efficiency (was Re: class implementation)

[Chris Marrin <chris@...>]

Mike Pall wrote:
> Hi,
>
> Mark Hamburg wrote:
>
> > Mike is correct that introducing the iterator function -- even as useful as
> > it is -- brings in memory allocation costs and hence is a lose for small
> > numbers of arguments.
>
>
> So, let's benchmark it. Here are the two ways to iterate over
> arguments (without doing anything with them):
>
> local function iterate_with_select(...)
>   local select = select
>   for j=1,1e6 do
>
>     for i=1,select('#', ...) do
>       local a = select(i, ...)
>     end
>
>   end
> end

Doesn't this have to call select('#',...) on every iteration? And since 
select is a function call, wouldn't:

    local n = select('#', ...)
    for i=1,n do
      local a = select(i, ...)
    end

give you a noticeable improvement?

--
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