On 16 March 2016 at 09:23, David B. Lamkins <da...@lamkins.net> wrote:
> On Tue, Mar 15, 2016 at 11:35:59AM +0800, Elias Mårtenson wrote: > > The lexical rewriter could be a plugin, but it could also be an APL > function. Imagine being able to assign an APL function to > quad-SOMETHINGOROTHER to define your own local syntax. You'd still be > running APL2 code under the covers, but you'd be able to define your own > syntax for anything that can be rewritten (presumably less conveniently) in > APL2. Remember that the rewriter would have full access to the underlying > APL2 interpreter, so you'd be able write entire programs to support the > processing of some new syntax. > > (If the above sounds familiar, it's probably because it's an amalgamation > of ideas from Lisp.) > It does indeed sound a lot like Lisp form rewriting. I'm all for this idea, and I'd be willing to make a test implementation of it, as long as someone (else) can can come up with a decent way of actually create a way to unambiguously state the input to be transformed (the equivalent of the DEFMACRO destructuring form in Lisp). > Also, quad-SOMETHINGOROTHER would be a nightmare in shared code unless > there was a good way to support localization (in the APL sense, not the > I18N sense). > The extensions would be part of the program itself, just like in Lisp. I don't see a problem here. > > Jürgen has previously explained that there are technical difficulties > > in expanding the character repertoire outside 255 characters, but I > > still feel this is one old limitation that deserves being eliminated. > > I understand why we need to limit quad-AV to 256 elements. But what about > composed characters? Would it be enough to alias the Unicode "compose" > codepoint to the ASCII "backspace" (that is already, I'm assuming, in > quad-AV...)? > I'm not entirely sure why Quad-AV even needs to exist in a modern program? We should be able to use all of Unicode to name our functions. Regards, Elias
