Macro doesn't work in the function.
- by avp
I have problems with following code: http://lisper.ru/apps/format/96
The problem is in "normalize" function, which does not work.
It fails on the fifth line: (zero-p a indexes i)
(defun normalize (a &optional indexes i)
"Returns normalized A."
(pragma
(format t "Data=~A ~A ~A" a indexes i)
(if (zero-p a indexes i)
a ;; cannot normalize empty vector
(let* ((mmm (format t "Zero?=~a" (zero-p a indexes i)))
(L (sqrt (+ (do-op-on * a :x a :x indexes i indexes i)
(do-op-on * a :y a :y indexes i indexes i)
(do-op-on * a :z a :z indexes i indexes i))))
(mmm (format t "L=~a" L))
(L (/ 1D0 L))
(mmm (format t "L=~a" L))) ; L=1/length(A)
(make-V3 (* (ref-of a :x indexes i) l)
(* (ref-of a :y indexes i) l)
(* (ref-of a :z indexes i) l))))))
in function "normalize" I call the macro "zero-p", which in turn calls macro "ref-of", which is the last in the chain.
(defmacro zero-p (v &optional indexes index)
"Checks if the vector is 'almost' zero length."
`(and (< (ref-of ,v :x ,indexes ,index) *min+*)
(< (ref-of ,v :y ,indexes ,index) *min+*)
(< (ref-of ,v :z ,indexes ,index) *min+*)
(> (ref-of ,v :x ,indexes ,index) *min-*)
(> (ref-of ,v :y ,indexes ,index) *min-*)
(> (ref-of ,v :z ,indexes ,index) *min-*)))
Here is ref-of:
(defmacro ref-of (values coordinate &optional indexes index)
"Please see DATA STRUCTURE for details."
(if indexes
(cond ((eq coordinate :x) `(aref ,values (aref ,indexes ,index)))
((eq coordinate :y) `(aref ,values (+ 1 (aref ,indexes ,index))))
((eq coordinate :z) `(aref ,values (+ 2 (aref ,indexes ,index))))
(T (error "The symbol ~S is not :X, :Y or :Z." coordinate)))
(cond ((eq coordinate :x) `(aref ,values 0))
((eq coordinate :y) `(aref ,values 1))
((eq coordinate :z) `(aref ,values 2))
(T (error "The symbol ~S is not :X, :Y or :Z." coordinate)))))
Also, in "normalize" I call the macro "do-op-on", which calls "ref-of" as well.
(defmacro do-op-on (op name1 coord1 name2 coord2 &optional is1 i1 is2 i2)
"Example: (do-op-on * A :x B :y i n) == A[i[n]].x*B.y"
`(,op (ref-of ,name1 ,coord1 ,is1 ,i1) (ref-of ,name2 ,coord2 ,is2 ,i2)))
As a result, instead of having this: (aref some-array 0) I have (aref NIL NIL) which is created in "ref-of".
I suppose that I lose the symbol A from the call (normalize A). I just feel that the symbol does not survive the macroexpanson. The thing is, macroexpansoin works in REPL for each macro independently.
Can anyone explain where is the mistake?
