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[Sbcl-help] Type declarations T and NIL for SB-PCL::VALUE conflict.

From: Leslie P. Polzer <leslie.polzer@gm...> - 2008-01-16 12:33

I have a class where one slot has type MYTYPE, being

(defvar *valid-items* (list 'item1 'item2))

(deftype mytype ()
  `(and symbol (member ,*valid-items*)))

which leads to the following:

; ==>
;   #'(LAMBDA (SB-PCL::VALUE)
;       (DECLARE (TYPE MYTYPE SB-PCL::VALUE)
;        (OPTIMIZE (SB-C:STORE-COVERAGE-DATA 0)))
;       SB-PCL::VALUE)
;
; caught WARNING:
;   The type declarations T and NIL for SB-PCL::VALUE conflict.
;   See also:
;     The SBCL Manual, Node "Handling of Types"

I don't get it. What's happening here?

  Leslie

-- 
My personal blog: http://blog.viridian-project.de/

Thread View

Thread	Author	Date
[Sbcl-help] Type declarations T and NIL for SB-PCL::VALUE conflict.	Leslie P. Polzer <leslie.polzer@gm...>

Re: [Sbcl-help] Type declarations T and NIL for SB-PCL::VALUE conflict.

From: Juho Snellman <jsnell@ik...> - 2008-01-16 12:56

"Leslie P. Polzer" <leslie.polzer@...> writes:

> I have a class where one slot has type MYTYPE, being
> 
> (defvar *valid-items* (list 'item1 'item2))
> 
> (deftype mytype ()
>   `(and symbol (member ,*valid-items*)))

Nothing will ever be both a symbol and a (member (item1 item2)). Did
you perhaps mean (member ,@*valid-items*)?

-- 
Juho Snellman

Re: [Sbcl-help] Type declarations T and NIL for SB-PCL::VALUE conflict.

From: Leslie P. Polzer <leslie.polzer@gm...> - 2008-01-16 13:20

> Nothing will ever be both a symbol and a (member (item1 item2)). Did
> you perhaps mean (member ,@*valid-items*)?

Yes, that was my intention. The little details often get me these days...

  Leslie

-- 
My personal blog: http://blog.viridian-project.de/