Possible to avoid reflection in this deftype in 1.3 alpha1?

[Andy Fingerhut]

The following program compiles and runs perfectly fine in both 1.2 and
1.3 alpha1. It has no reflection warnings in 1.2, but it does in 1.3
alpha1. I have tried several variations, but I haven't yet been able
to figure out how to write type declarations that avoid reflection in
1.3 alpha1. Does anyone know whether this is a bug?

Or perhaps code like this ought to be structured completely
differently in order to avoid reflection, and it was just a fluke that
it worked in 1.2?

Thanks,
Andy

(ns nbody
(:gen-class))

(set! *warn-on-reflection* true)

(definterface IBody
(^double x [])
(^double y [])
(^double z [])
(^double dist [other]))

(deftype Body [^{:unsynchronized-mutable true :tag double} x
^{:unsynchronized-mutable true :tag double} y
^{:unsynchronized-mutable true :tag double} z ]
IBody
(x [this] x)
(y [this] y)
(z [this] z)
(dist [this other]
(let [^Body nbody other
dx (- x (.x nbody)) ; first reflection warning here
dy (- y (.y nbody)) ; second here
dz (- z (.z nbody)) ; third here
dsq (+ (* dx dx)
(+ (* dy dy)
(* dz dz)))]
(Math/sqrt dsq))))

(defn -main [& args]
(let [b (Body. 0 0 0)]
(println "pos:" (.x b) (.y b) (.z b))))

[Stuart Halloway]

That's weird. I see no reflection warnings when loading this on 1.3 alpha 1.

Stu

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[Andy Fingerhut]

OK, so I happened to stumble across a fix to my program, but I still
wonder whether this is intentional behavior in 1.3 alpha1 or not.

If I change the name 'nbody' in these lines:

> (let [^Body nbody other
> dx (- x (.x nbody)) ; first reflection warning here
> dy (- y (.y nbody)) ; second here
> dz (- z (.z nbody)) ; third here

to some name that is not the name of the namespace, like 'nbo', then
the reflection warnings go away:

> (let [^Body nbo other
> dx (- x (.x nbo)) ; first reflection warning here
> dy (- y (.y nbo)) ; second here
> dz (- z (.z nbo)) ; third here

If I then change the ns declaration at the top to "ns nbo", the
reflection warnings come back again.

Easy to avoid the problem, once you know.

Andy

[Andy Fingerhut]

I don't know if it makes a difference, but I was doing AOT compilation
on a file nbody.clj containing the program in my message.

I replied to my own message with a workaround that it seems to be
related to the variable 'nbody' having the same name as the one in the
'ns' declaration.

Thanks,
Andy