[Sbcl-help] string type uncertainty?

[Pascal B. <pj...@in...>]

What declarations are needed to compile this without type uncertainty?

(DEFUN COPY (SRC FROM-SRC DST FROM-DST LENGTH)
  (DECLARE (STRING SRC DST) (FIXNUM FROM-SRC FROM-DST LENGTH))
  (WHILE (< 0 LENGTH)
    (SETF (CHAR DST FROM-DST) (CHAR SRC FROM-SRC))
    (INCF FROM-DST)
    (INCF FROM-SRC)
    (DECF LENGTH))
  ) ;;COPY


;     (SETF (CHAR COM.INFORMATIMAGO.COMMON-LISP.PACKAGE::DST
;               COM.INFORMATIMAGO.COMMON-LISP.PACKAGE::FROM-DST)
;           (CHAR COM.INFORMATIMAGO.COMMON-LISP.PACKAGE::SRC
;                 COM.INFORMATIMAGO.COMMON-LISP.PACKAGE::FROM-SRC))
; --> SB-KERNEL:%CHARSET SB-KERNEL:%ASET LET* SB-KERNEL:HAIRY-DATA-VECTOR=
-SET=20
; --> MULTIPLE-VALUE-BIND MULTIPLE-VALUE-CALL=20
; =3D=3D>
;   (SB-KERNEL:%DATA-VECTOR-AND-INDEX ARRAY SB-INT:INDEX)
;=20
; note: unable to
;         optimize
;       due to type uncertainty:
;         The first argument is a BASE-STRING, not a SIMPLE-ARRAY.

(Typical usage of COPY would be:
      (let ((dst (make-string 10)))
         (copy "hello" 0 dst 0 5)
         (copy "world" 0 dst 5 5)
         dst)
)

--=20
__Pascal_Bourguignon__                   http://www.informatimago.com/
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