[Larceny-users] define-macro library

[Eduardo Cavazos]

Eduardo Cavazos wrote:

> ----------------------------------------------------------------------
>  > (define (sq n) (* n n))
> 
>  > (define-macro (test-macro-sq a) `(list (sq ,a)))
> 
>  > (test-macro-sq 10)
> 
> Syntax violation: invalid reference
> 
> No binding available for sq in library (define-macro)
> ----------------------------------------------------------------------

So... the way I got around this problem is to *not* put 'define-macro' 
in it's own Larceny library (i.e. *.sls) file.

What I'm doing right now is evaluating this at the toplevel in ERR5RS mode.

----------------------------------------------------------------------
(import

  (for (rnrs base) run expand)

  (for (rnrs syntax-case) run expand)

  (for (rnrs bytevectors) run expand)

  (for (rnrs control) run expand)

  (rnrs io simple)
  (err5rs records syntactic)
  (err5rs load)
  (primitives current-directory file-exists?)

  )

(define-syntax define-macro
    (lambda (x)
      (syntax-case x ()
        ((_ (name . args) . body)
         (syntax (define-macro name (lambda args . body))))
        ((_ name transformer)
         (syntax
          (define-syntax name
            (lambda (y)
              (syntax-case y ()
                 ((_ . args)
                  (datum->syntax
                   (syntax _)
                   (apply transformer
                          (syntax->datum (syntax args)))))))))))))
----------------------------------------------------------------------

Of course, I don't copy and paste that into the listener each time... I 
have that in a file called 'src/boot/larceny/larceny.scm' and I start 
larceny like this:

     cat src/boot/larceny/larceny.scm - | larceny -err5rs

Kludges FTW! :-)

Anywho, the above works for my purposes for now. I hope that eventually 
there'll be an implementation of 'define-macro' available in the Larceny 
distribution which is blessed by the core team.

Ed