[dev-context] A few questions

[Aditya Mahajan]

On Fri, 7 Aug 2009, Hans Hagen wrote:

>>>> i get the feeling we're moving towards latex3 (brr), before this happens 
>>>> drop the whole
>>>> thing and i don't like \getvariable in this context anyway
>>> 
>>> there was a presentation about this ltx3 low level syntax and i definitely 
>>> don't want to have something like that; it's more that in context we have 
>>> this system of [optional]{whatever} that we might want to support
>> 
>> me neither, the latex3 system is too complicated and one has to remember 
>> what n, N, x ... means etc.
>
> indeed, and also kind of redundant as the name should denote the usage, i.e. 
> imagine that in e.g. lua we did  myfunction_takes_num_and_num
>
> i would not be surprised if it's also quite slow (esp when used in core code) 
> and core code is not used by users anyway
>
>> there are a few interesting things like namespaces for module/macros but 
>> that's not worth the effort they take
>
> indeed, but keep in mind that in context we seldom have other interfaces that 
> [] and {}, no optoinal * etc

One good thing with LaTeX 3 syntax is that something like

\DeclareDocumentCommand\foo { o o m } will be (from what I understand) 
equivalent to

\def\foo
  {\dodoubleempty\dofoo}

\def\dofoo[#1][#2]#3{...}

When I started using context, I was surprised that context did not have 
anything for optional arguments. We could have something like

\definesinglearugment\foo[#1]#2{...}

to be equal to

\def\foo{\dosingleargument\dofoo}
\def\dofoo[#1]#2{...}

and

\definesingleempty\foo[#1]#2{...]

to be equal to

\def\foo{\dosingleempty\dofoo}
\def\dofoo[#1]#2{...}

and similar things for \definedoublearugment, \definetripleargument, etc. 
I am not convinced that this is a good thing, but using something like 
this in the core may result in a 10% reduction in the code size and might 
kill a few dodos :)

Aditya