Hi Racketeers, Just getting started in the whole Racket thing - it seems like the nicest Lisp around at this point in time. A big reason for me wanting to get to know Lisp/Scheme/Racket was to play around with macros and it seems like Racket takes the idea to its logical conclusion going beyond hygenic macros with its whole language building features. However I have to say I have found it a little difficult to fully get my head around some of the ideas (phase levels etc) so I suppose i could at least understand why some people yearn for the simplicity of "defmacro" despite its flaws. I think i just need to plow through the references some more.
Anyway for mostly self-educational purposes I was trying to get a particular macro working and cant seem to do it. The inspiration behind it was that I was looking at the Racket Object System and I kind of felt like there was a little less typing to get a class going. I'm also a bit of a fan of light feeling OO systems like in Python that dont really care about enforcing privacy and just wanted to give the class declaration a name and then have a public variable/property available without the need to write 3 lines. In other words instead of typing all this: (class<http://docs.racket-lang.org/reference/createclass.html#(form._((lib._racket/private/class-internal..rkt)._class))> object%<http://docs.racket-lang.org/reference/createclass.html#(def._((lib._racket/private/class-internal..rkt)._object~25))> (init<http://docs.racket-lang.org/reference/createclass.html#(form._((lib._racket/private/class-internal..rkt)._init))> size) ; initialization argument (define<http://docs.racket-lang.org/reference/define.html#(form._((lib._racket/private/base..rkt)._define))> current-size size) ; field (define/public<http://docs.racket-lang.org/reference/createclass.html#(form._((lib._racket/private/class-internal..rkt)._define/public))> (get-size) current-size) ............. I wanted to be able to write something like: (init+ size) that would expand to something like: (init<http://docs.racket-lang.org/reference/createclass.html#(form._((lib._racket/private/class-internal..rkt)._init))> size) ; initialization argument (define<http://docs.racket-lang.org/reference/define.html#(form._((lib._racket/private/base..rkt)._define))> size+ size) ; field (define/public<http://docs.racket-lang.org/reference/createclass.html#(form._((lib._racket/private/class-internal..rkt)._define/public))> (size++) size+) even better would be an expansion of (init+ size) to: (init<http://docs.racket-lang.org/reference/createclass.html#(form._((lib._racket/private/class-internal..rkt)._init))> size++) ; initialization argument (define<http://docs.racket-lang.org/reference/define.html#(form._((lib._racket/private/base..rkt)._define))> size+ size++) ; field (define/public<http://docs.racket-lang.org/reference/createclass.html#(form._((lib._racket/private/class-internal..rkt)._define/public))> (size) size+) so that I had a public accesssor method that had the same name as the original declaration. As mentioned this is mainly a self-educational exercise. I know there is "init-field" that would pretty much take care of this and there are some prototype based Object systems in Planet but I just wanted to see if this was possible and how/why not. Anyway hope its not too stupid a question.
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