Re: _SELF and _SUPER

[Duane Leslie <parakleta@...>]

> On 7 Aug 2016, at 06:36, Sean Conner <sean@conman.org> wrote:
> 
> It was thus said that the Great Soni L. once stated:
>> 
>>> On 06/08/16 05:30 PM, Sean Conner wrote:
>>>  You just need a Y-combinator:
>>> 
>>>    function Y(f)
>>>      local function g(...) return f(g,...) end
>>>      return g
>>>    end
>>> 
>>>    print(Y(function(rec, x)
>>>            if x < 2 then
>>>                return 1
>>>            else
>>>                return x * rec(x-1)
>>>            end
>>>        end)(5))
>>> 
>>>  That will allow you to call an anonymous function recurively from within
>>> the anonymous function.  No need for _SELF in this case.
>> 
>> That doesn't solve the dynamic variable indexing issue.
> 
>  Oh, I'm sorry I failed to read your mind again.  I thought that was what
> _SUPER was for.  I'm so sorry you have to reject MY ATTEMPT to give you
> something you could use and grovel that I have to have your proposal
> explained to me like I'm five.
> 
>  -spc (Why do I even bother?)

I appreciated the explanation.  I like learning ways to 'upgrade' a language with clever syntactic sugar without having to change the underlying language.  It gives the option to use much more powerful paradigms within a simpler language.

I personally think this _SELF/_SUPER thing comes unravelled with the requirement that it support dynamic variable lookups.  That adds an overhead to the runtime which I don't agree with.  If it was only statically declared lookups then it could be easily implemented as a custom parser that would actually generate standard byte-code.

I miss that metalua didn't make the jump to 5.2/5.3, I'm often tempted to bring it up to date but for now I still find it easier to just modify the parser directly.  I think if metalua was current a lot of these feature requests could just be resolved with a metalua script.