Re: nyacc support for extension languages

[Matt Wette]

On 08/19/2018 02:28 PM, Joshua Branson wrote:

> Matt Wette <address@hidden> writes:
>
> > I am working on providing a module to add to the nyacc distribution for
> > the purpose of generating extension languages, and putting together a few
> > extensions for demo.  So far I'm playing with javascript and matlab.
> > These languages use a "nx-" prefix to designate them as "nyacc extension".
> > One can interpret "nx" to also mean "not exactly", so "nx-matlab" is not
> > exactly MATLAB.  It has taken some work to get my yacc like parser to
> > parse expressions instead of files, so some work has gone into updating
> > the nyacc parser.  nyacc/parse.scm now has parser generators that provide
> > an #:interactive option and more robust default-reductions for generating
> > parsers which work well in interactive mode.
> This is super cool!  Is the goal to eventually make it exactly
> matlab/exactly javascript?  Or will there always be some portability
> issues?
I thought about this a bit.  I think hope for 100% compatibility is not there.
For example, javascript strings are always 16bit code points, whereas Guile 
strings
are either 8-bit characters or 32-bit code points.

Also, I'd like to "fix" some problems in javascript.  For example

var a = 1;
if (1) {
  var a = 2;
}
a => 2
if (1) {
  let a = 3;
}
a => 2

I have made "var" inside blocks illegal. And "let" is not standard, but I'm 
adding it.

I also want to make the underlying data model consistent among languages, so 
that may
take some "massaging" of the language def's.

Matt