[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: AW: vector-unzip

This page is part of the web mail archives of SRFI 43 from before July 7th, 2015. The new archives for SRFI 43 contain all messages, not just those from before July 7th, 2015.




On Tuesday, April 22, 2003, at 01:22 AM, Michael Burschik wrote:

To quote from the reference implementation:

;; Convenient abbreviations for common unzipping.
(define (vector-unzip1 vec)
  (check-arg vector? vec 'vector-unzip1)
  (vector-unzip vec 0))
(define (vector-unzip2 vec)
  (check-arg vector? vec 'vector-unzip2)
  (vector-unzip vec 1))
(define (vector-unzip3 vec)
  (check-arg vector? vec 'vector-unzip3)
  (vector-unzip vec 2))
(define (vector-unzip4 vec)
  (check-arg vector? vec 'vector-unzip4)
  (vector-unzip vec 3))
(define (vector-unzip5 vec)
  (check-arg vector? vec 'vector-unzip5)
  (vector-unzip vec 5))

This would seem to corroborate my assumption that (vector-unzipn vec) ==
(vector-unzip vec (- n 1)).

But even if I am mistaken, my main point was the definition of
vector-unzip5, which breaks the pattern.

To be more accurate, VECTOR-UNZIP[1-4] were wrong, while VECTOR-UNZIP5 was written correctly. I'll get a new copy of the reference implementation and the
SRFI document up soon, fixing this all.

Regards

Michael Burschik