Success!  I've included the final solution here for completeness and 
community contribution.


   1. Thanks, Didier-- your last bit got me on the right path.
   2. Thanks, Gregg-- it turns out gen-class does recognize that syntax, if 
   quoted, like so:  
   
   #^{:static true} [score ["[Ljava.lang.Number;" "[Ljava.lang.Object;"] 
   "[[Ljava.lang.Number;"]
   
   
I preferred to put the data manipulation into the clojure layer to ensure 
that it's acting as consistent resource provider, allowing a "natural" 
interpretation in the host language (in this case, JavaScript).  Note that 
in addition to interpreting the input into a Clojurey frame, it also 
reframed the output back into a JavaScripty frame.

Here's the final solution:


*Clojure*

(ns score
"docs omitted"
  (:gen-class

    :name score

    :prefix "javascript-compat-" 

    :methods [                  
              #^{:static true} [
                score
                ["[Ljava.lang.Double;" "[Ljava.lang.Object;"]
                clojure.lang.PersistentObject]]))



(defn score
"do mathy stuff"
  [subject context]

                (do-something-fancy subject context)) 
 

(defn javascript-compat-score
  [subject context]
  (into []
    (score (into [] subject)
           (mapv #(into [] %) context))))



*JavaScript*

const java = require('java');
function genFixture () {
  return new Array(12).fill(parseFloat(Math.random().toFixed(2)));
}

console.log("Generating fixtures...");
var data = genFixture();
var contex = new Array(10).fill(1);
context.forEach((d,i) => { context[i] = genFixture(); });

// This produces, for example, the following fixtures:
// data: [ 0.89, 0.89, 0.89, 0.89, 0.89, 0.89, 0.89, 0.89, 0.89, 0.89, 
0.89, 0.89 ]
// context: [
//   [ 0.35, 0.35, 0.35, 0.35, 0.35, 0.35, 0.35, 0.35, 0.35, 0.35, 0.35, 
0.35 ],
//   [ 0.85, 0.85, 0.85, 0.85, 0.85, 0.85, 0.85, 0.85, 0.85, 0.85, 0.85, 
0.85 ],
//   ...
//   [ 0.31, 0.31, 0.31, 0.31, 0.31, 0.31, 0.31, 0.31, 0.31, 0.31, 0.31, 
0.31 ]]

java.classpath.push("./java/score-0.2.1-standalone.jar");
console.log("Importing class ...");
var score = java.import('score');

console.log("Attempting to run score.scoreSync(data, context)");
try {
  var s = score.scoreSync(data, context);
console.log("S is", s.tail);
} catch (e) {
  console.log("Got an error:", e);
}


Output

Generating fixtures...
Importing class ...
Attempting to run score.scoreSync(data, context)
S is [ 0.1945, 0.2495 ]



Thanks again! 

-Sir

On Monday, August 7, 2017 at 2:29:52 PM UTC-4, Didier wrote:
>
> Arrays in Clojure are different to Lists, and its probably why when you 
> pass arrays to the score fn, that things don't work 100%.
>
> If you can coerce those arrays to a java list it would probably work. You 
> can do that in js, but if that doesn't work or seem easy, you could have 
> your -score wrapper do it too.
>
> To convert the 2d array do:
>
> (mapv #(into [] %) the-array)
>
> To convert the 1d array do:
>
> (into [] the-array)
>
> And to convert the return of score from a list back to an array do:
>
> (to-array the-list) or (to-array-2d the-list-of-list)
>
>

-- 
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to clojure@googlegroups.com
Note that posts from new members are moderated - please be patient with your 
first post.
To unsubscribe from this group, send email to
clojure+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/clojure?hl=en
--- 
You received this message because you are subscribed to the Google Groups 
"Clojure" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to clojure+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to