Hi all -
I'm experiencing some unexpected behavior with protocols. Stripping
out extraneous details...
;;;;;;;;;;;;;
(ns my.ns1
...)
(defprotocol pro-1
...)
(deftype T1 [...]
pro-1
...)
(defn fun [p]
^{:pre [(satisfies? pro-1 p)
]
}
...)
;;;;;;;;;;;;;;;;
Then in another file:
(ns my.ns2
(:use [my.ns1]))
(deftype T2 [...]
pro-1
...)
...
;;;;;;;;;;;;;;;;;;;;;;;;;
Then in a third file
(ns my.ns3
(:use
[my.ns1]
[my.ns2]))
(defn ...
(let [x (T2. ...)
]
...
(fun x)
...))
This throws an error saying that 'x' does not satisfy the protocol.
Looking at the documented source of 'satisfies?', I see that this
amounts to asking
(instance? (:on-interface pro-1) x), which => false.
(:on-interface pro-1) => my.ns1.pro_1
but (class x) => T2 and (supers T2) => #{my.ns1.pro_1
java.lang.object}
Also, just to check (instance? T2 x) => true.
What am I not getting here? How can x be an instance of T2 and not be
an instance of one of its supers?
--
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
