On Thu 20 Feb 2020 17:19, Ludovic Courtès <l...@gnu.org> writes:
> Of all the scm_tc7_ values listed in ‘scm.h’, the following are not
> explicitly listed (so they go to the default case that hashes the first
> word):
Reformatting your list so I can check one by one :)
> variable,
> hashtable,
> fluid,
> dynamic_state,
> frame,
> atomic_box,
> program,
> vm_cont,
> weak_set,
> weak_table,
> port
No equal? implementation, so should hashq() instead.
> bytevector,
> array,
> bitvector,
These have equal? implementations, and what's more, a bitvector can
equal? an array... I think we have another bug!
;; Project 2d array as 1d array (scm_tc7_array)
(define x
(make-shared-array #2b((#t #t #t)) (lambda (i) (list 0 i)) '(0 2)))
;; scm_tc7_bitvector
(define y #*111)
(equal? x y) ;; => #t
(equal? (hash x #xffffffff) (hash y #xffffffff)) ;; => #f
Similarly for 1-d scm_tc7_array versus regular vectors, bytevectors,
etc.
Fixing this will not be straightforward... I think basically 1d arrays
need some special hashing logic so that e.g. vectors and 1d arrays hash
to the same thing.
> stringbuf,
> values,
These are never exposed to Scheme, and never compared using equal?
AFAIU. No need for special cases.
Basically I think the tc7 case should default to hashq, and include
special cases for the ones that have equal? implementations or which
have read syntax.
Sound right to you?
Andy
