On Jun 28, 12:41 am, "Stephen C. Gilardi" <[email protected]> wrote:
> On Jun 28, 2009, at 12:07 AM, Handkea fumosa wrote:
>
> > user=> (list? '(1 2 3))
> > true
> > user=> (list? (cons 4 '(1 2 3)))
> > false
>
> user=> (doc cons)
> -------------------------
> clojure.core/cons
> ([x seq])
> Returns a new seq where x is the first element and seq is
> the rest.
> nil
> user=> (cons 4 '(1 2 3))
> (4 1 2 3)
> user=> (seq? (cons 4 '(1 2 3)))
> true
> user=> (first (cons 4 '(1 2 3)))
> 4
> user=> (rest (cons 4 '(1 2 3)))
> (1 2 3)
> user=> (list? (rest (cons 4 '(1 2 3))))
> true
> user=>
>
> cons is acting according to its documentation.
It's list? that isn't.
> Some of the roles played by lists in other Lisps are played by seqs in
> Clojure. Also, in Clojure a list is not a linked list of cons cells.
> Roughly speaking, a Clojure list is a linked list of lists:
>
> user=> (list? (rest (rest (rest '(1 2 3 4 5 6 7)))))
> true
My current workaround is to use
(defn fixed-list? [obj]
(and (sequential? obj) (not (vector? obj))))
This gives me the desired semantics: it's a list if it's a ()
collection rather than a [], {}, or #{} collection.
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to [email protected]
Note that posts from new members are moderated - please be patient with your
first post.
To unsubscribe from this group, send email to
[email protected]
For more options, visit this group at
http://groups.google.com/group/clojure?hl=en
-~----------~----~----~----~------~----~------~--~---
