cyclone/scheme/cyclone/macros.sld

(define-library (scheme cyclone macros)
  (import (scheme base)
          (scheme cyclone util))
  ; TODO: really need export-all for these cyclone libs!!
  (export
    define-syntax?
    macro:macro?
    macro:expand
    macro:add!
    macro:get-defined-macros
  )
  (begin
    ;; A list of all macros defined by the program/library being compiled
    (define *macro:defined-macros* '())

    (define (macro:add! name body)
      (set! *macro:defined-macros* 
        (cons (cons name body) *macro:defined-macros*))
      #t)

    (define (macro:get-defined-macros) *macro:defined-macros*)

    ;; Macro section
    ;; TODO: place this in another module? could speed development
    (define (define-syntax? exp)
      (tagged-list? 'define-syntax exp))

    (define (macro:macro? exp defined-macros) (assoc (car exp) defined-macros))
    (define (macro:expand exp defined-macros)
      (let ((rename (lambda (sym) ;; TODO: not good enough, need to actually rename, and keep same results if
                      sym))       ;; the same symbol is renamed more than once
            (compare? (lambda (sym-a sym-b)  ;; TODO: the compare function from exrename.
                         (eq? sym-a sym-b))) ;; this may need to be more sophisticated
           )
        ;(cond
        ;  ;; compiled macro
        ;  ;((macro? (car exp))
        ;  ;  ((car exp)
        ;  ;   exp
        ;  ;   rename
        ;  ;   compare?))
        ;  (else
            (let ((macro (assoc (car exp) defined-macros)))

;TODO: restructure this to use eval if the macro is not a proc.
;      then can try passing in an environment with create-environment.
;      once eval is extended to work with macros, this could allow it to
;      expand a macro contained within another

              ;; assumes ER macro
              (if macro
                ((Cyc-get-cvar (cdr macro))
                  ;exp 
                  ; could be a raw lambda, if that is the case try quoting it
                  (if (macro? (Cyc-get-cvar (cdr macro)))
                    exp
                    (list 'quote exp))
                  rename
                  compare?)
                exp))));)) ;; TODO: error instead??

    ; TODO: get macro name, transformer
    ; TODO: base off of syntactic closures instead of ER macros??
    ; TODO: let-syntax forms
  ))