Re: Upcoming changes in Lua 5.4

["Soni \"They/Them\" L." <fakedme@...>]

On 2018-01-09 12:48 AM, Xavier Wang wrote:
> 云风 Cloud Wu <cloudwu@gmail.com <mailto:cloudwu@gmail.com>>于2018年1月9日 
> 周二上午9:55写道：
>
>     Roberto Ierusalimschy <roberto@inf.puc-rio.br
>     <mailto:roberto@inf.puc-rio.br>>于2018年1月8日周一 下午8:36写道：
>
>         vararg functions in critical paths often. Several (most?)
>         vararg functions
>         have to create tables (or pay the price of 'select') anyway.
>
>
>     Can this one avoid vararg create tables in lua 5.4 ?
>
>     function  print_with_tag(tag)
>       return function(...)
>         return print(tag, ...)
>       end
>     end
>
>
> No. It have _ARG tables create when each time the inner function 
> called. ... will be compiled as a bytecode based unpack.
> --
> regards,
> Xavier Wang.

I definitely have questions about the performance of this:

table.pack(some, things, or_a, function_call, here)

vs this:

(function(...) return _ARGS end)(same, as, above)

Since the latter creates a table in bytecode.

I also wonder about the performance of this: 
https://github.com/SoniEx2/Stuff/tree/master/lua/Forth

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