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3 points by nex3 5872 days ago | link | parent

There shouldn't be anything in arc2 that isn't in Anarki except maybe a couple srv.arc improvements that are more or less a subset of the improvements made earlier in Anarki.

I did a full merge of arc2 when it was released (see http://www.arclanguage.org/item?id=3427), and when there were conflicts, generally favored PG's solutions to the ones already present. If there is anything missing, I'd love to know what it is.



2 points by sacado 5872 days ago | link

For example, arc-call was change a little, for performance reasons I guess :

  (define (ac-call fn args env)
   (let ((macfn (ac-macro? fn)))
    (cond (macfn
           (ac-mac-call macfn args env))
          ((and (pair? fn) (eqv? (car fn) 'fn))
           `(,(ac fn env) ,@(map (lambda (x) (ac x env)) args)))
          ((= (length args) 0)
           `(ar-funcall0 ,(ac fn env) ,@(map (lambda (x) (ac x env)) args)))
          ((= (length args) 1)
           `(ar-funcall1 ,(ac fn env) ,@(map (lambda (x) (ac x env)) args)))
          ((= (length args) 2)
           `(ar-funcall2 ,(ac fn env) ,@(map (lambda (x) (ac x env)) args)))
          ((= (length args) 3)
           `(ar-funcall3 ,(ac fn env) ,@(map (lambda (x) (ac x env)) args)))
          ((= (length args) 4)
           `(ar-funcall4 ,(ac fn env) ,@(map (lambda (x) (ac x env)) args)))
          (#t
           `(ar-apply ,(ac fn env)
                      (list ,@(map (lambda (x) (ac x env)) args)))))))
Instead of the code currently in anarki, taken from arc1 :

  (define (ac-call fn args env)
  (let ((macfn (ac-macro? fn)))
    (if macfn
      (ac-mac-call macfn args env)
      (let ((afn (ac fn env))
            (aargs (map (lambda (x) (ac x env)) args))
            (nargs (length args)))
        (cond
          ((eqv? (xcar fn) 'fn)
           `(,afn ,@aargs))
          ((and (>= nargs 0) (<= nargs 4))
           `(,(string->symbol (string-append "ar-funcall" (number->string nargs)))
              ,afn ,@aargs))
          (#t
           `(ar-apply ,afn (list ,@aargs))))))))
That one is not crucial, as it only brings a minor performance gain in most of the cases. However, I'm more skeptical about that :

  (define (ac-fn args body env)
   (if (ac-complex-args? args)
      (ac-complex-fn args body env)
      `(lambda ,(let ((a (ac-denil args))) (if (eqv? a 'nil) '() a))
         'nil
         ,@(ac-body body (append (ac-arglist args) env)))))
Versus the code from Anarki, still the original arc1's version :

  (define (ac-fn args body env)
   (if (ac-complex-args? args)
      (ac-complex-fn args body env)
      `(lambda ,(let ((a (ac-denil args))) (if (eqv? a 'nil) '() a))
         ,@(ac-body* body (append (ac-arglist args) env)))))
Isn't it a bug fix ? The one someone told about, with '(), () and nil not being always equivalent ? If so, that's more problematic. I tried to merge these codes together, but it was obviously broken and was reverted later in the git.

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5 points by nex3 5872 days ago | link

Those do seem to be mistakes. It looks like this might have been caused by the Windows-newlining of ac.scm, which screwed with the Git history a little. I'll change these to the arc2 versions... if you see any other inconsistencies, let me know.

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2 points by nex3 5872 days ago | link

I've changed ac-call to the arc2 version, but I think you're wrong about ac-fn. The following:

  (define (ac-fn args body env)
   (if (ac-complex-args? args)
      (ac-complex-fn args body env)
      `(lambda ,(let ((a (ac-denil args))) (if (eqv? a 'nil) '() a))
         'nil
         ,@(ac-body body (append (ac-arglist args) env)))))
is how it's been in arc0, arc1, and arc2. The following:

  (define (ac-fn args body env)
   (if (ac-complex-args? args)
      (ac-complex-fn args body env)
      `(lambda ,(let ((a (ac-denil args))) (if (eqv? a 'nil) '() a))
         ,@(ac-body* body (append (ac-arglist args) env)))))
is unique to Anarki, and was added as part of a patch for MzScheme compatibility.

After getting rid of all the trailing-whitespace-removal that was clogging the diffs, I think ac-call was the only non-purposeful difference between ac.scm in Anarki and arc2. Let me know if you notice any more, though.

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