Array machinery for the JavaScript compiler.

24 files changed, 541 insertions, 284 deletions

diff --git a/lux-js/source/program.lux b/lux-js/source/program.lux
index 00bdd2ef8..77b23e2f7 100644
--- a/lux-js/source/program.lux
+++ b/lux-js/source/program.lux
@@ -29,7 +29,10 @@
      ["." name]
      [phase
       [macro (#+ Expander)]
-      ["." extension/bundle]
+      ["." extension #_
+       ["#/." bundle]
+       ["." analysis #_
+        ["#/." js]]]
       ["." generation
        ["." js
         ["." runtime]
@@ -42,8 +45,11 @@
 
 (import: #long java/lang/String)
 
+(import: #long (java/lang/Class a))
+
 (import: #long java/lang/Object
-  (toString [] java/lang/String))
+  (toString [] java/lang/String)
+  (getClass [] (java/lang/Class java/lang/Object)))
 
 (import: #long java/lang/Long
   (intValue [] java/lang/Integer))
@@ -220,8 +226,9 @@
 (exception: null-has-no-lux-representation)
 (exception: undefined-has-no-lux-representation)
 
-(exception: (unknown-kind-of-js-object {object java/lang/Object})
+(exception: (unknown-kind-of-host-object {object java/lang/Object})
   (exception.report
+   ["Class" (java/lang/Object::toString (java/lang/Object::getClass object))]
    ["Object" (java/lang/Object::toString object)]))
 
 (exception: (cannot-apply-a-non-function {object java/lang/Object})
@@ -272,23 +279,27 @@
       jdk/nashorn/api/scripting/ScriptObjectMirror
       (Maybe (Array java/lang/Object)))
   (if (jdk/nashorn/api/scripting/JSObject::isArray js-object)
-    (let [init-num-keys (.nat (jdk/nashorn/api/scripting/ScriptObjectMirror::size js-object))]
-      (loop [num-keys init-num-keys
-             idx 0
+    (let [num-keys (.nat (jdk/nashorn/api/scripting/ScriptObjectMirror::size js-object))]
+      (loop [idx 0
              output (: (Array java/lang/Object)
-                       (array.new init-num-keys))]
+                       (array.new num-keys))]
         (if (n/< num-keys idx)
           (case (jdk/nashorn/api/scripting/JSObject::getMember (%n idx) js-object)
             (#.Some member)
-            (case (lux-object member)
-              (#error.Success parsed-member)
-              (recur num-keys (inc idx) (array.write idx (:coerce java/lang/Object parsed-member) output))
+            (case (host.check jdk/nashorn/internal/runtime/Undefined member)
+              (#.Some _)
+              (recur (inc idx) output)
+
+              #.None
+              (case (lux-object member)
+                (#error.Success parsed-member)
+                (recur (inc idx) (array.write idx (:coerce java/lang/Object parsed-member) output))
 
-              (#error.Failure error)
-              #.None)
+                (#error.Failure error)
+                #.None))
 
             #.None
-            (recur num-keys (inc idx) output))
+            (recur (inc idx) output))
           (#.Some output))))
     #.None))
 
@@ -335,10 +346,10 @@
                   #.None
                   (if (jdk/nashorn/api/scripting/JSObject::isFunction js-object)
                     (exception.return js-object)
-                    (exception.throw unknown-kind-of-js-object (:coerce java/lang/Object js-object))))))
+                    (exception.throw ..unknown-kind-of-host-object (:coerce java/lang/Object js-object))))))
             #.None)
           ## else
-          (exception.throw unknown-kind-of-js-object (:coerce java/lang/Object js-object))
+          (exception.throw ..unknown-kind-of-host-object (:coerce java/lang/Object js-object))
           )))
 
 (def: (ensure-macro macro)
@@ -449,7 +460,9 @@
 
 (program: [{service /cli.service}]
   (/.compiler @.js
+              ".js"
               ..expander
+              analysis/js.bundle
               ..platform
               extension.bundle
               extension/bundle.empty
diff --git a/new-luxc/source/program.lux b/new-luxc/source/program.lux
index 4d6d63835..2ec090903 100644
--- a/new-luxc/source/program.lux
+++ b/new-luxc/source/program.lux
@@ -21,7 +21,10 @@
    [tool
     [compiler
      [phase
-      ["." macro (#+ Expander)]]
+      ["." macro (#+ Expander)]
+      ["." extension #_
+       [analysis
+        ["#" jvm]]]]
      [default
       ["." platform (#+ Platform)]]]]]
   [program
@@ -159,7 +162,9 @@
 
 (program: [{service /cli.service}]
   (/.compiler @.jvm
+              ".jvm"
               ..expander
+              extension.bundle
               ..jvm
               ..bundle
               jvmS.bundle
diff --git a/stdlib/source/lux/control/concurrency/atom.lux b/stdlib/source/lux/control/concurrency/atom.lux
index d16b485f7..d15ccfc28 100644
--- a/stdlib/source/lux/control/concurrency/atom.lux
+++ b/stdlib/source/lux/control/concurrency/atom.lux
@@ -1,27 +1,30 @@
 (.module:
   [lux #*
-   [host (#+ import:)]
+   ["." host]
    ["@" target]
    [abstract
     [monad (#+ do)]]
    [control
     ["." function]
     ["." io (#- run)]]
+   [data
+    [collection
+     ["." array]]]
    [type
     abstract]])
 
 (`` (for {(~~ (static @.old))
-          (import: #long (java/util/concurrent/atomic/AtomicReference a)
+          (host.import: #long (java/util/concurrent/atomic/AtomicReference a)
             (new [a])
             (get [] a)
             (compareAndSet [a a] boolean))
 
           (~~ (static @.jvm))
-          (import: #long (java/util/concurrent/atomic/AtomicReference a)
+          (host.import: #long (java/util/concurrent/atomic/AtomicReference a)
             (new [a])
             (get [] a)
-            (compareAndSet [a a] boolean))
-          }))
+            (compareAndSet [a a] boolean))}
+         (as-is)))
 
 (`` (abstract: #export (Atom a)
       {#.doc "Atomic references that are safe to mutate concurrently."}
@@ -31,6 +34,9 @@
 
             (~~ (static @.jvm))
             (java/util/concurrent/atomic/AtomicReference a)
+
+            (~~ (static @.js))
+            (array.Array a)
             })
 
       (def: #export (atom value)
@@ -40,6 +46,9 @@
 
                             (~~ (static @.jvm))
                             (java/util/concurrent/atomic/AtomicReference::new value)
+
+                            (~~ (static @.js))
+                            ("js array write" 0 value ("js array new" 1))
                             })))
 
       (def: #export (read atom)
@@ -49,6 +58,9 @@
 
                   (~~ (static @.jvm))
                   (java/util/concurrent/atomic/AtomicReference::get (:representation atom))
+
+                  (~~ (static @.js))
+                  ("js array read" 0 (:representation atom))
                   })))
 
       (def: #export (compare-and-swap current new atom)
@@ -60,7 +72,13 @@
 
                   (~~ (static @.jvm))
                   (java/util/concurrent/atomic/AtomicReference::compareAndSet current new (:representation atom))
-                  })))
+
+                  (~~ (static @.js))
+                  (let [old ("js array read" 0 (:representation atom))]
+                    (if (is? old current)
+                      (exec ("js array write" 0 new (:representation atom))
+                        true)
+                      false))})))
       ))
 
 (def: #export (update f atom)
diff --git a/stdlib/source/lux/control/concurrency/process.lux b/stdlib/source/lux/control/concurrency/process.lux
index fc5ad2050..7cb569ee9 100644
--- a/stdlib/source/lux/control/concurrency/process.lux
+++ b/stdlib/source/lux/control/concurrency/process.lux
@@ -1,7 +1,7 @@
 (.module:
   [lux #*
    ["@" target]
-   ["." host (#+ import: object)]
+   ["." host]
    [abstract
     ["." monad (#+ do)]]
    [control
@@ -14,44 +14,44 @@
    ["." atom (#+ Atom)]])
 
 (`` (for {(~~ (static @.old))
-          (as-is (import: #long java/lang/Object)
+          (as-is (host.import: #long java/lang/Object)
 
-                 (import: #long java/lang/Runtime
+                 (host.import: #long java/lang/Runtime
                    (#static getRuntime [] java/lang/Runtime)
                    (availableProcessors [] int))
 
-                 (import: #long java/lang/Runnable)
+                 (host.import: #long java/lang/Runnable)
 
-                 (import: #long java/util/concurrent/TimeUnit
+                 (host.import: #long java/util/concurrent/TimeUnit
                    (#enum MILLISECONDS))
                  
-                 (import: #long java/util/concurrent/Executor
+                 (host.import: #long java/util/concurrent/Executor
                    (execute [java/lang/Runnable] #io void))
 
-                 (import: #long (java/util/concurrent/ScheduledFuture a))
+                 (host.import: #long (java/util/concurrent/ScheduledFuture a))
 
-                 (import: #long java/util/concurrent/ScheduledThreadPoolExecutor
+                 (host.import: #long java/util/concurrent/ScheduledThreadPoolExecutor
                    (new [int])
                    (schedule [java/lang/Runnable long java/util/concurrent/TimeUnit] #io (java/util/concurrent/ScheduledFuture java/lang/Object))))
 
           (~~ (static @.jvm))
-          (as-is (import: #long java/lang/Object)
+          (as-is (host.import: #long java/lang/Object)
 
-                 (import: #long java/lang/Runtime
+                 (host.import: #long java/lang/Runtime
                    (#static getRuntime [] java/lang/Runtime)
                    (availableProcessors [] int))
 
-                 (import: #long java/lang/Runnable)
+                 (host.import: #long java/lang/Runnable)
 
-                 (import: #long java/util/concurrent/TimeUnit
+                 (host.import: #long java/util/concurrent/TimeUnit
                    (#enum MILLISECONDS))
                  
-                 (import: #long java/util/concurrent/Executor
+                 (host.import: #long java/util/concurrent/Executor
                    (execute [java/lang/Runnable] #io void))
 
-                 (import: #long (java/util/concurrent/ScheduledFuture a))
+                 (host.import: #long (java/util/concurrent/ScheduledFuture a))
 
-                 (import: #long java/util/concurrent/ScheduledThreadPoolExecutor
+                 (host.import: #long java/util/concurrent/ScheduledThreadPoolExecutor
                    (new [int])
                    (schedule [java/lang/Runnable long java/util/concurrent/TimeUnit] #io (java/util/concurrent/ScheduledFuture java/lang/Object))))}
          
@@ -91,7 +91,7 @@
 (def: #export (schedule milli-seconds action)
   (-> Nat (IO Any) (IO Any))
   (`` (for {(~~ (static @.old))
-            (let [runnable (object [] [java/lang/Runnable]
+            (let [runnable (host.object [] [java/lang/Runnable]
                              []
                              (java/lang/Runnable [] (run self) void
                                                  (io.run action)))]
@@ -101,7 +101,7 @@
                                                                               runner)))
 
             (~~ (static @.jvm))
-            (let [runnable (object [] [java/lang/Runnable]
+            (let [runnable (host.object [] [java/lang/Runnable]
                              []
                              (java/lang/Runnable [] (run self) void
                                                  (io.run action)))]
@@ -111,10 +111,12 @@
                                                                               runner)))}
            
            ## Default
-           (atom.update (|>> (#.Cons {#creation ("lux io current-time")
-                                      #delay milli-seconds
-                                      #action action}))
-                        runner))))
+           (do io.monad
+             [_ (atom.update (|>> (#.Cons {#creation (.nat ("lux io current-time"))
+                                           #delay milli-seconds
+                                           #action action}))
+                             runner)]
+             (wrap [])))))
 
 (`` (for {(~~ (static @.old))
           (as-is)
@@ -137,15 +139,17 @@
 
                         _
                         (do @
-                          [#let [now ("lux io current-time")
+                          [#let [now (.nat ("lux io current-time"))
                                  [ready pending] (list.partition (function (_ process)
                                                                    (|> (get@ #creation process)
                                                                        (n/+ (get@ #delay process))
                                                                        (n/<= now)))
                                                                  processes)]
-                           swapped? (atom.compare-and-swap! processes pending runner)]
+                           swapped? (atom.compare-and-swap processes pending runner)]
                           (if swapped?
-                            (monad.seq @ ready)
+                            (do @
+                              [_ (monad.map @ (get@ #action) ready)]
+                              (wrap []))
                             (error! (ex.construct cannot-continue-running-processes []))))
                         ))))
                 )))
diff --git a/stdlib/source/lux/control/thread.lux b/stdlib/source/lux/control/thread.lux
index b27e56395..7dfa4c490 100644
--- a/stdlib/source/lux/control/thread.lux
+++ b/stdlib/source/lux/control/thread.lux
@@ -40,7 +40,10 @@
                      (:coerce (primitive "java.lang.Long"))
                      "jvm object cast"
                      "jvm conversion long-to-int")
-                 (:representation box))}))))
+                 (:representation box))
+
+                (~~ (static @.js))
+                ("js array read" 0 (:representation box))}))))
 
   (def: #export (write value box)
     (All [a] (-> a (All [!] (-> (Box ! a) (Thread ! Any)))))
diff --git a/stdlib/source/lux/control/writer.lux b/stdlib/source/lux/control/writer.lux
index 866fe0b18..1b82bf0c7 100644
--- a/stdlib/source/lux/control/writer.lux
+++ b/stdlib/source/lux/control/writer.lux
@@ -62,10 +62,9 @@
     (do monad
       [[l1 Mla] (`` (for {(~~ (static @.old))
                           (: (($ 1) (Writer ($ 0) (($ 1) (Writer ($ 0) ($ 2)))))
-                             MlMla)
-
-                          (~~ (static @.jvm))
-                          MlMla}))
+                             MlMla)}
+                         ## On new compiler
+                         MlMla))
        [l2 a] Mla]
       (wrap [(:: monoid compose l1 l2) a]))))
 
diff --git a/stdlib/source/lux/data/collection/array.lux b/stdlib/source/lux/data/collection/array.lux
index cac39d65f..b109fc2fb 100644
--- a/stdlib/source/lux/data/collection/array.lux
+++ b/stdlib/source/lux/data/collection/array.lux
@@ -40,7 +40,10 @@
                   !int
                   "jvm array new object"
                   (: <array-type>)
-                  :assume)})))
+                  :assume)
+
+              (~~ (static @.js))
+              ("js array new" size)})))
 
   (def: #export (size array)
     (All [a] (-> (Array a) Nat))
@@ -54,7 +57,10 @@
                   "jvm conversion int-to-long"
                   "jvm object cast"
                   (: <index-type>)
-                  (:coerce Nat))})))
+                  (:coerce Nat))
+
+              (~~ (static @.js))
+              ("js array length" array)})))
 
   (def: #export (read index array)
     (All [a]
@@ -72,7 +78,13 @@
                                 ("jvm array read object" (!int index)))]
                   (if ("jvm object null?" value)
                     #.None
-                    (#.Some (:assume value))))}))
+                    (#.Some (:assume value))))
+
+                (~~ (static @.js))
+                (let [output ("js array read" index array)]
+                  (if ("js undefined?" output)
+                    #.None
+                    (#.Some output)))}))
       #.None))
 
   (def: #export (write index value array)
@@ -85,7 +97,10 @@
               (|> array
                   (:coerce <array-type>)
                   ("jvm array write object" (!int index) (:coerce <elem-type> value))
-                  :assume)})))
+                  :assume)
+
+              (~~ (static @.js))
+              ("js array write" index value array)})))
 
   (def: #export (delete index array)
     (All [a]
@@ -95,7 +110,10 @@
                 (write index (:assume ("jvm object null")) array)
 
                 (~~ (static @.jvm))
-                (write index (:assume (: <elem-type> ("jvm object null"))) array)}))
+                (write index (:assume (: <elem-type> ("jvm object null"))) array)
+
+                (~~ (static @.js))
+                ("js array delete" index array)}))
       array))
   )
 
diff --git a/stdlib/source/lux/data/collection/tree/zipper.lux b/stdlib/source/lux/data/collection/tree/zipper.lux
index f6a8ad8f0..cf6020ffe 100644
--- a/stdlib/source/lux/data/collection/tree/zipper.lux
+++ b/stdlib/source/lux/data/collection/tree/zipper.lux
@@ -98,16 +98,14 @@
                              (: (-> (Tree ($ 0)) (Tree ($ 0)))
                                 (set@ #//.children (list@compose (list.reverse (get@ #lefts zipper))
                                                                  (#.Cons (get@ #node zipper)
-                                                                         (get@ #rights zipper)))))
-                             
-                             (~~ (static @.jvm))
-                             (:share [a]
-                                     {(Zipper a)
-                                      zipper}
-                                     {(-> (Tree a) (Tree a))
-                                      (set@ #//.children (list@compose (list.reverse (get@ #lefts zipper))
-                                                                       (#.Cons (get@ #node zipper)
-                                                                               (get@ #rights zipper))))})}))
+                                                                         (get@ #rights zipper)))))}
+                            (:share [a]
+                                    {(Zipper a)
+                                     zipper}
+                                    {(-> (Tree a) (Tree a))
+                                     (set@ #//.children (list@compose (list.reverse (get@ #lefts zipper))
+                                                                      (#.Cons (get@ #node zipper)
+                                                                              (get@ #rights zipper))))})))
              parent)))
 
 (def: #export (start zipper)
@@ -203,10 +201,8 @@
            (function (_ children)
              (list& (`` (for {(~~ (static @.old))
                               (: (Tree ($ 0))
-                                 (//.tree [value {}]))
-                              
-                              (~~ (static @.jvm))
-                              (//.tree [value {}])}))
+                                 (//.tree [value {}]))}
+                             (//.tree [value {}])))
                     children))
            zipper))
 
@@ -217,10 +213,8 @@
              (list@compose children
                            (list (`` (for {(~~ (static @.old))
                                            (: (Tree ($ 0))
-                                              (//.tree [value {}]))
-                                           
-                                           (~~ (static @.jvm))
-                                           (//.tree [value {}])})))))
+                                              (//.tree [value {}]))}
+                                          (//.tree [value {}]))))))
            zipper))
 
 (def: #export (remove zipper)
@@ -252,10 +246,8 @@
                    (update@ <side> (function (_ side)
                                      (#.Cons (`` (for {(~~ (static @.old))
                                                        (: (Tree ($ 0))
-                                                          (//.tree [value {}]))
-                                                       
-                                                       (~~ (static @.jvm))
-                                                       (//.tree [value {}])}))
+                                                          (//.tree [value {}]))}
+                                                      (//.tree [value {}])))
                                              side)))))))]
 
   [insert-left  #lefts]
@@ -270,21 +262,19 @@
      #node (//@map f (get@ #node fa))}))
 
 (`` (for {(~~ (static @.old))
-          (as-is)
-          
-          (~~ (static @.jvm))
-          (structure: #export comonad (CoMonad Zipper)
-            (def: &functor ..functor)
-
-            (def: unwrap (get@ [#node #//.value]))
-
-            (def: (split [parent lefts rights node])
-              (let [tree-splitter (: (All [a] (-> (Tree a) (Tree (Zipper a))))
-                                     (function (tree-splitter tree)
-                                       {#//.value (zip tree)
-                                        #//.children (list@map tree-splitter
-                                                               (get@ #//.children tree))}))]
-                {#parent (maybe@map split parent)
-                 #lefts (list@map tree-splitter lefts)
-                 #rights (list@map tree-splitter rights)
-                 #node (tree-splitter node)})))}))
+          (as-is)}
+         (structure: #export comonad (CoMonad Zipper)
+           (def: &functor ..functor)
+
+           (def: unwrap (get@ [#node #//.value]))
+
+           (def: (split [parent lefts rights node])
+             (let [tree-splitter (: (All [a] (-> (Tree a) (Tree (Zipper a))))
+                                    (function (tree-splitter tree)
+                                      {#//.value (zip tree)
+                                       #//.children (list@map tree-splitter
+                                                              (get@ #//.children tree))}))]
+               {#parent (maybe@map split parent)
+                #lefts (list@map tree-splitter lefts)
+                #rights (list@map tree-splitter rights)
+                #node (tree-splitter node)})))))
diff --git a/stdlib/source/lux/host.js.lux b/stdlib/source/lux/host.js.lux
index 7fd2a3420..ecca052e2 100644
--- a/stdlib/source/lux/host.js.lux
+++ b/stdlib/source/lux/host.js.lux
@@ -1,24 +1,25 @@
 (.module:
   [lux #*
-   [abstract
-    monad]
    [control
     ["p" parser
      ["s" code (#+ Parser)]]]
    [data
     [collection
-     ["." list #* ("#;." fold)]]]
+     ["." list ("#@." fold)]]]
+   [type
+    abstract]
    [macro (#+ with-gensyms)
-    ["." code]
-    [syntax (#+ syntax:)]]])
+    [syntax (#+ syntax:)]
+    ["." code]]])
 
 (template [<name> <type>]
-  [(type: #export <name> (#.Primitive <type> #.Nil))]
+  [(abstract: #export <name> {} Any)]
 
-  [Object    "object"]
-  [Function  "function"]
-  [Symbol    "symbol"]
-  [Undefined "undefined"]
+  [Object]
+  [Function]
+  [Symbol]
+  [Null]
+  [Undefined]
   )
 
 (template [<name> <type>]
@@ -28,62 +29,3 @@
   [Number  Frac]
   [Boolean Bit]
   )
-
-## [Syntax]
-(syntax: #export (set! field-name field-value object)
-  {#.doc (doc "A way to set fields from objects."
-              (set! "foo" +1234 some-object))}
-  (wrap (list (` ("js set-field" (~ object) (~ field-name) (~ field-value))))))
-
-(syntax: #export (delete! field-name object)
-  {#.doc (doc "A way to delete fields from objects."
-              (delete! "foo" some-object))}
-  (wrap (list (` ("js delete-field" (~ object) (~ field-name))))))
-
-(syntax: #export (get field-name type object)
-  {#.doc (doc "A way to get fields from objects."
-              (get "ceil" (ref "Math"))
-              (get "ceil" (-> Frac Frac) (ref "Math")))}
-  (wrap (list (` (:coerce (~ type)
-                          ("js get-field" (~ object) (~ field-name)))))))
-
-(syntax: #export (object {kvs (p.some (p.and s.any s.any))})
-  {#.doc (doc "A way to create JavaScript objects."
-              (object)
-              (object "foo" foo "bar" (inc bar)))}
-  (wrap (list (list;fold (function (_ [k v] object)
-                           (` (set! (~ k) (~ v) (~ object))))
-                         (` ("js object"))
-                         kvs))))
-
-(syntax: #export (ref {name s.text}
-                      {type (p.maybe s.any)})
-  {#.doc (doc "A way to refer to JavaScript variables."
-              (ref "document")
-              (ref "Math.ceil" (-> Frac Frac)))}
-  (wrap (list (` (:coerce (~ (default (' ..Object) type))
-                          ("js ref" (~ (code.text name))))))))
-
-(template [<name> <proc> <doc>]
-  [(syntax: #export (<name>)
-     {#.doc (doc <doc>
-                 (<name>))}
-     (wrap (list (` (<proc>)))))]
-
-  [null  "js null"      "Null object reference."]
-  [undef "js undefined" "Undefined."]
-  )
-
-(syntax: #export (call! {shape (p.or ($_ p.and s.any (s.tuple (p.some s.any)) (p.maybe s.any))
-                                     ($_ p.and s.any s.text (s.tuple (p.some s.any)) (p.maybe s.any)))})
-  {#.doc (doc "A way to call JavaScript functions and methods."
-              (call! (ref "Math.ceil") [+123.45])
-              (call! (ref "Math") "ceil" [+123.45]))}
-  (case shape
-    (#.Left [function args ?type])
-    (wrap (list (` (:coerce (~ (default (' ..Object) ?type))
-                            ("js call" (~ function) (~+ args))))))
-    
-    (#.Right [object field args ?type])
-    (wrap (list (` (:coerce (~ (default (' ..Object) ?type))
-                            ("js object-call" (~ object) (~ (code.text field)) (~+ args))))))))
diff --git a/stdlib/source/lux/math.lux b/stdlib/source/lux/math.lux
index 1340f31d0..41627aca9 100644
--- a/stdlib/source/lux/math.lux
+++ b/stdlib/source/lux/math.lux
@@ -66,7 +66,31 @@
                    (-> Frac Frac Frac)
                    (|> ("jvm member invoke static" "java.lang.Math" "pow"
                         ["D" (!double subject)] ["D" (!double param)])
-                       !frac)))}))
+                       !frac)))
+
+          (~~ (static @.js))
+          (as-is (template [<name> <method>]
+                   [(def: #export <name>
+                      (-> Frac Frac)
+                      (|>> ("js apply" ("js constant" <method>)) (:coerce Frac)))]
+
+                   [cos   "Math.cos"]
+                   [sin   "Math.sin"]
+                   [tan   "Math.tan"]
+
+                   [acos  "Math.acos"]
+                   [asin  "Math.asin"]
+                   [atan  "Math.atan"]
+                   
+                   [exp   "Math.exp"]
+                   [log   "Math.log"]
+                   
+                   [ceil  "Math.ceil"]
+                   [floor "Math.floor"]
+                   )
+                 (def: #export (pow param subject)
+                   (-> Frac Frac Frac)
+                   (:coerce Frac ("js apply" ("js constant" "Math.pow") subject param))))}))
 
 (def: #export (round input)
   (-> Frac Frac)
diff --git a/stdlib/source/lux/target/js.lux b/stdlib/source/lux/target/js.lux
index c34f806f8..526621236 100644
--- a/stdlib/source/lux/target/js.lux
+++ b/stdlib/source/lux/target/js.lux
@@ -276,14 +276,14 @@
     (-> Var Expression Statement)
     (:abstraction (format "var " (:representation name) " = " (:representation value) ..statement-suffix)))
 
-  (def: #export (set name value)
-    (-> Location Expression Statement)
-    (:abstraction (format (:representation name) " = " (:representation value) ..statement-suffix)))
-
   (def: #export (set' name value)
     (-> Location Expression Expression)
     (:abstraction (..argument (format (:representation name) " = " (:representation value)))))
 
+  (def: #export (set name value)
+    (-> Location Expression Statement)
+    (:abstraction (format (:representation (set' name value)) ..statement-suffix)))
+
   (def: #export (throw message)
     (-> Expression Statement)
     (:abstraction (format "throw " (:representation message) ..statement-suffix)))
@@ -292,9 +292,13 @@
     (-> Expression Statement)
     (:abstraction (format "return " (:representation value) ..statement-suffix)))
 
+  (def: #export (delete' value)
+    (-> Location Expression)
+    (:abstraction (format "delete " (:representation value))))
+
   (def: #export (delete value)
     (-> Location Statement)
-    (:abstraction (format "delete " (:representation value) ..statement-suffix)))
+    (:abstraction (format (:representation (delete' value)) ..statement-suffix)))
 
   (def: #export (if test then! else!)
     (-> Expression Statement Statement Statement)
diff --git a/stdlib/source/lux/tool/compiler/default/init.lux b/stdlib/source/lux/tool/compiler/default/init.lux
index 1f650634f..1a8d10474 100644
--- a/stdlib/source/lux/tool/compiler/default/init.lux
+++ b/stdlib/source/lux/tool/compiler/default/init.lux
@@ -19,7 +19,7 @@
   ["." //
    ["#." syntax (#+ Aliases)]
    ["#." evaluation]
-   ["#/" // (#+ Instancer)
+   ["/#" // (#+ Instancer)
     ["#." analysis]
     ["#." synthesis]
     ["#." statement (#+ Requirements)]
@@ -48,10 +48,11 @@
    #.version //.version
    #.mode #.Build})
 
-(def: #export (state target expander host generate generation-bundle host-statement-bundle program)
+(def: #export (state target expander host-analysis host generate generation-bundle host-statement-bundle program)
   (All [anchor expression statement]
     (-> Text
         Expander
+        ///analysis.Bundle
         (generation.Host expression statement)
         (generation.Phase anchor expression statement)
         (generation.Bundle anchor expression statement)
@@ -61,8 +62,9 @@
   (let [synthesis-state [synthesisE.bundle ///synthesis.init]
         generation-state [generation-bundle (generation.state host)]
         eval (//evaluation.evaluator expander synthesis-state generation-state generate)
-        analysis-state [(analysisE.bundle eval) (///analysis.state (..info target) host)]]
-    [(dictionary.merge (luxS.bundle expander program)
+        analysis-state [(analysisE.bundle eval host-analysis)
+                        (///analysis.state (..info target) host)]]
+    [(dictionary.merge (luxS.bundle expander host-analysis program)
                        host-statement-bundle)
      {#///statement.analysis {#///statement.state analysis-state
                               #///statement.phase (analysisP.phase expander)}
diff --git a/stdlib/source/lux/tool/compiler/default/platform.lux b/stdlib/source/lux/tool/compiler/default/platform.lux
index 5dc5105f2..3e086e813 100644
--- a/stdlib/source/lux/tool/compiler/default/platform.lux
+++ b/stdlib/source/lux/tool/compiler/default/platform.lux
@@ -16,7 +16,7 @@
   ["." // #_
    ["#." init]
    ["#." syntax]
-   ["#/" //
+   ["/#" //
     ["#." analysis]
     ["#." statement]
     ["#." phase
@@ -56,10 +56,11 @@
                   <State+> (as-is (///statement.State+ anchor expression statement))
                   <Bundle> (as-is (generation.Bundle anchor expression statement))]
 
-  (def: #export (initialize target expander platform generation-bundle host-statement-bundle program)
+  (def: #export (initialize target expander host-analysis platform generation-bundle host-statement-bundle program)
     (All <type-vars>
       (-> Text
           Expander
+          ///analysis.Bundle
           <Platform>
           <Bundle>
           (///statement.Bundle anchor expression statement)
@@ -70,6 +71,7 @@
         ///statement.lift-generation
         (///phase.run' (//init.state target
                                      expander
+                                     host-analysis
                                      (get@ #host platform)
                                      (get@ #phase platform)
                                      generation-bundle
@@ -104,9 +106,9 @@
     ##   (io.fail error))
     )
 
-  (def: #export (compile expander platform configuration archive state)
+  (def: #export (compile partial-host-extension expander platform configuration archive state)
     (All <type-vars>
-      (-> Expander <Platform> Configuration Archive <State+> (! (Error [Archive <State+>]))))
+      (-> Text Expander <Platform> Configuration Archive <State+> (! (Error [Archive <State+>]))))
     (let [monad (get@ #&monad platform)
           source-module (get@ #cli.module configuration)
           compiler (:share [anchor expression statement]
@@ -128,6 +130,7 @@
               [input (context.read monad
                                    (get@ #&file-system platform)
                                    (get@ #cli.sources configuration)
+                                   partial-host-extension
                                    module)
                ## _ (&io.prepare-module target-dir (get@ #cli.module configuration))
                ## _ (write-module target-dir file-name (get@ #cli.module configuration) module outputs)
diff --git a/stdlib/source/lux/tool/compiler/meta/io/context.lux b/stdlib/source/lux/tool/compiler/meta/io/context.lux
index bd1efd73b..454487cce 100644
--- a/stdlib/source/lux/tool/compiler/meta/io/context.lux
+++ b/stdlib/source/lux/tool/compiler/meta/io/context.lux
@@ -36,23 +36,6 @@
   Extension
   ".lux")
 
-(def: partial-host-extension
-  Extension
-  (`` (for {(~~ (static @.common-lisp)) ".cl"
-            (~~ (static @.js))          ".js"
-            (~~ (static @.old))         ".jvm"
-            (~~ (static @.jvm))         ".jvm"
-            (~~ (static @.lua))         ".lua"
-            (~~ (static @.php))         ".php"
-            (~~ (static @.python))      ".py"
-            (~~ (static @.r))           ".r"
-            (~~ (static @.ruby))        ".rb"
-            (~~ (static @.scheme))      ".scm"})))
-
-(def: full-host-extension
-  Extension
-  (format partial-host-extension lux-extension))
-
 (def: #export (path system context module)
   (All [m] (-> (file.System m) Context Module Path))
   (|> module
@@ -78,22 +61,23 @@
         (#error.Failure error)
         (find-source-file monad system contexts' module extension)))))
 
-(def: #export (find-any-source-file monad system contexts module)
+(def: #export (find-any-source-file monad system contexts partial-host-extension module)
   (All [!]
-    (-> (Monad !) (file.System !) (List Context) Module
+    (-> (Monad !) (file.System !) (List Context) Text Module
         (! (Error [Path (File !)]))))
-  (do monad
-    [outcome (find-source-file monad system contexts module ..full-host-extension)]
-    (case outcome
-      (#error.Success output)
-      (wrap outcome)
+  (let [full-host-extension (format partial-host-extension lux-extension)]
+    (do monad
+      [outcome (find-source-file monad system contexts module full-host-extension)]
+      (case outcome
+        (#error.Success output)
+        (wrap outcome)
 
-      (#error.Failure error)
-      (find-source-file monad system contexts module ..lux-extension))))
+        (#error.Failure error)
+        (find-source-file monad system contexts module ..lux-extension)))))
 
-(def: #export (read monad system contexts module)
+(def: #export (read monad system contexts partial-host-extension module)
   (All [!]
-    (-> (Monad !) (file.System !) (List Context) Module
+    (-> (Monad !) (file.System !) (List Context) Text Module
         (! (Error Input))))
   (do (error.with monad)
     [## TODO: Get rid of both ":share"s ASAP
@@ -101,7 +85,7 @@
                        {(Monad !)
                         monad}
                        {(! (Error [Path (File !)]))
-                        (find-any-source-file monad system contexts module)})
+                        (find-any-source-file monad system contexts partial-host-extension module)})
      #let [[path file] (:share [!]
                                {(Monad !)
                                 monad}
diff --git a/stdlib/source/lux/tool/compiler/name.lux b/stdlib/source/lux/tool/compiler/name.lux
index 252d57051..093d934cb 100644
--- a/stdlib/source/lux/tool/compiler/name.lux
+++ b/stdlib/source/lux/tool/compiler/name.lux
@@ -30,7 +30,8 @@
         ["<"] "_LT"
         [">"] "_GT"
         ["~"] "_TI"
-        ["|"] "_PI"]
+        ["|"] "_PI"
+        [" "] "_SP"]
        (text.from-code char))))
 
 (def: #export (normalize name)
diff --git a/stdlib/source/lux/tool/compiler/phase/extension/analysis.lux b/stdlib/source/lux/tool/compiler/phase/extension/analysis.lux
index 694f0345f..df378eebf 100644
--- a/stdlib/source/lux/tool/compiler/phase/extension/analysis.lux
+++ b/stdlib/source/lux/tool/compiler/phase/extension/analysis.lux
@@ -1,20 +1,16 @@
-(.`` (.module:
-       [lux #*
-        ["@" target]
-        [data
-         [collection
-          ["." dictionary]]]]
-       [////
-        [default
-         [evaluation (#+ Eval)]]
-        [analysis (#+ Bundle)]]
-       ["." / #_
-        ["#." lux]
-        ["#." (~~ (.for {"{old}" jvm
-                         "JVM" jvm}))]]))
+(.module:
+  [lux #*
+   [data
+    [collection
+     ["." dictionary]]]]
+  [////
+   [default
+    [evaluation (#+ Eval)]]
+   [analysis (#+ Bundle)]]
+  ["." / #_
+   ["#." lux]])
 
-(def: #export (bundle eval)
-  (-> Eval Bundle)
-  (dictionary.merge (`` (for {(~~ (static @.old)) /jvm.bundle
-                              (~~ (static @.jvm)) /jvm.bundle}))
+(def: #export (bundle eval host-specific)
+  (-> Eval Bundle Bundle)
+  (dictionary.merge host-specific
                     (/lux.bundle eval)))
diff --git a/stdlib/source/lux/tool/compiler/phase/extension/analysis/js.lux b/stdlib/source/lux/tool/compiler/phase/extension/analysis/js.lux
new file mode 100644
index 000000000..d8285532b
--- /dev/null
+++ b/stdlib/source/lux/tool/compiler/phase/extension/analysis/js.lux
@@ -0,0 +1,146 @@
+(.module:
+  [lux #*
+   [abstract
+    ["." monad (#+ do)]]
+   [control
+    ["<>" parser
+     ["<c>" code (#+ Parser)]]
+    pipe]
+   [data
+    [collection
+     ["." array (#+ Array)]
+     ["." dictionary]]]
+   [type
+    ["." check]]
+   [target
+    ["_" js]]]
+  ["." // #_
+   ["#." lux (#+ custom)]
+   ["/#" //
+    ["#." bundle]
+    ["/#" // ("#@." monad)
+     [analysis
+      [".A" type]]
+     ["/#" // #_
+      ["#." analysis (#+ Analysis Operation Phase Handler Bundle)]]]]])
+
+(def: array::new
+  Handler
+  (custom
+   [<c>.any
+    (function (_ extension phase lengthC)
+      (do ////.monad
+        [lengthA (typeA.with-type Nat
+                   (phase lengthC))
+         [var-id varT] (typeA.with-env check.var)
+         _ (typeA.infer (type (Array varT)))]
+        (wrap (#/////analysis.Extension extension (list lengthA)))))]))
+
+(def: array::length
+  Handler
+  (custom
+   [<c>.any
+    (function (_ extension phase arrayC)
+      (do ////.monad
+        [[var-id varT] (typeA.with-env check.var)
+         arrayA (typeA.with-type (type (Array varT))
+                  (phase arrayC))
+         _ (typeA.infer Nat)]
+        (wrap (#/////analysis.Extension extension (list arrayA)))))]))
+
+(def: array::read
+  Handler
+  (custom
+   [(<>.and <c>.any <c>.any)
+    (function (_ extension phase [indexC arrayC])
+      (do ////.monad
+        [indexA (typeA.with-type Nat
+                  (phase indexC))
+         [var-id varT] (typeA.with-env check.var)
+         arrayA (typeA.with-type (type (Array varT))
+                  (phase arrayC))
+         _ (typeA.infer varT)]
+        (wrap (#/////analysis.Extension extension (list indexA arrayA)))))]))
+
+(def: array::write
+  Handler
+  (custom
+   [($_ <>.and <c>.any <c>.any <c>.any)
+    (function (_ extension phase [indexC valueC arrayC])
+      (do ////.monad
+        [indexA (typeA.with-type Nat
+                  (phase indexC))
+         [var-id varT] (typeA.with-env check.var)
+         valueA (typeA.with-type varT
+                  (phase valueC))
+         arrayA (typeA.with-type (type (Array varT))
+                  (phase arrayC))
+         _ (typeA.infer (type (Array varT)))]
+        (wrap (#/////analysis.Extension extension (list indexA valueA arrayA)))))]))
+
+(def: array::delete
+  Handler
+  (custom
+   [($_ <>.and <c>.any <c>.any)
+    (function (_ extension phase [indexC arrayC])
+      (do ////.monad
+        [indexA (typeA.with-type Nat
+                  (phase indexC))
+         [var-id varT] (typeA.with-env check.var)
+         arrayA (typeA.with-type (type (Array varT))
+                  (phase arrayC))
+         _ (typeA.infer (type (Array varT)))]
+        (wrap (#/////analysis.Extension extension (list indexA arrayA)))))]))
+
+(def: bundle::array
+  Bundle
+  (<| (///bundle.prefix "array")
+      (|> ///bundle.empty
+          (///bundle.install "new" array::new)
+          (///bundle.install "length" array::length)
+          (///bundle.install "read" array::read)
+          (///bundle.install "write" array::write)
+          (///bundle.install "delete" array::delete)
+          )))
+
+(def: js::constant
+  Handler
+  (custom
+   [<c>.text
+    (function (_ extension phase name)
+      (do ////.monad
+        [_ (typeA.infer Any)]
+        (wrap (#/////analysis.Extension extension (list (/////analysis.text name))))))]))
+
+(def: js::apply
+  Handler
+  (custom
+   [($_ <>.and <c>.any (<>.some <c>.any))
+    (function (_ extension phase [abstractionC inputsC])
+      (do ////.monad
+        [abstractionA (typeA.with-type Any
+                        (phase abstractionC))
+         inputsA (monad.map @ (|>> phase (typeA.with-type Any)) inputsC)
+         _ (typeA.infer Any)]
+        (wrap (#/////analysis.Extension extension (list& abstractionA inputsA)))))]))
+
+(def: js::undefined?
+  Handler
+  (custom
+   [<c>.any
+    (function (_ extension phase [valueC])
+      (do ////.monad
+        [valueA (typeA.with-type Any
+                  (phase valueC))
+         _ (typeA.infer Bit)]
+        (wrap (#/////analysis.Extension extension (list valueA)))))]))
+
+(def: #export bundle
+  Bundle
+  (<| (///bundle.prefix "js")
+      (|> ///bundle.empty
+          (///bundle.install "constant" js::constant)
+          (///bundle.install "apply" js::apply)
+          (///bundle.install "undefined?" js::undefined?)
+          (dictionary.merge bundle::array)
+          )))
diff --git a/stdlib/source/lux/tool/compiler/phase/extension/analysis/lux.lux b/stdlib/source/lux/tool/compiler/phase/extension/analysis/lux.lux
index 51402fad8..48401f0c6 100644
--- a/stdlib/source/lux/tool/compiler/phase/extension/analysis/lux.lux
+++ b/stdlib/source/lux/tool/compiler/phase/extension/analysis/lux.lux
@@ -90,31 +90,32 @@
        _ (<>.fail (exception.construct ..char-text-must-be-size-1 [raw])))))
 
  (def: lux::syntax-char-case!
-   (..custom [($_ <>.and
-                  <c>.any
-                  (<c>.tuple (<>.some (<>.and (<c>.tuple (<>.many ..text-char))
-                                              <c>.any)))
-                  <c>.any)
-              (function (_ extension-name phase [input conditionals else])
-                (do ////.monad
-                  [input (typeA.with-type text.Char
-                           (phase input))
-                   expectedT (///.lift macro.expected-type)
-                   conditionals (monad.map @ (function (_ [cases branch])
-                                               (do @
-                                                 [branch (typeA.with-type expectedT
-                                                           (phase branch))]
-                                                 (wrap [cases branch])))
-                                           conditionals)
-                   else (typeA.with-type expectedT
-                          (phase else))]
-                  (wrap (|> conditionals
-                            (list@map (function (_ [cases branch])
-                                        (/////analysis.tuple
-                                         (list (/////analysis.tuple (list@map (|>> /////analysis.nat) cases))
-                                               branch))))
-                            (list& input else)
-                            (#/////analysis.Extension extension-name)))))])))
+   (..custom
+    [($_ <>.and
+         <c>.any
+         (<c>.tuple (<>.some (<>.and (<c>.tuple (<>.many ..text-char))
+                                     <c>.any)))
+         <c>.any)
+     (function (_ extension-name phase [input conditionals else])
+       (do ////.monad
+         [input (typeA.with-type text.Char
+                  (phase input))
+          expectedT (///.lift macro.expected-type)
+          conditionals (monad.map @ (function (_ [cases branch])
+                                      (do @
+                                        [branch (typeA.with-type expectedT
+                                                  (phase branch))]
+                                        (wrap [cases branch])))
+                                  conditionals)
+          else (typeA.with-type expectedT
+                 (phase else))]
+         (wrap (|> conditionals
+                   (list@map (function (_ [cases branch])
+                               (/////analysis.tuple
+                                (list (/////analysis.tuple (list@map (|>> /////analysis.nat) cases))
+                                      branch))))
+                   (list& input else)
+                   (#/////analysis.Extension extension-name)))))])))
 
 ## "lux is" represents reference/pointer equality.
 (def: lux::is
diff --git a/stdlib/source/lux/tool/compiler/phase/extension/statement/lux.lux b/stdlib/source/lux/tool/compiler/phase/extension/statement/lux.lux
index 0ae210fa5..af49f8ee1 100644
--- a/stdlib/source/lux/tool/compiler/phase/extension/statement/lux.lux
+++ b/stdlib/source/lux/tool/compiler/phase/extension/statement/lux.lux
@@ -127,9 +127,9 @@
             (synthesize codeA))]
     (definition' generate name code//type codeS)))
 
-(def: (refresh expander)
+(def: (refresh expander host-analysis)
   (All [anchor expression statement]
-    (-> Expander (Operation anchor expression statement Any)))
+    (-> Expander /////analysis.Bundle (Operation anchor expression statement Any)))
   (do ////.monad
     [[bundle state] ////.get-state
      #let [eval (/////evaluation.evaluator expander
@@ -140,11 +140,11 @@
                      (update@ [#/////statement.analysis #/////statement.state]
                               (: (-> /////analysis.State+ /////analysis.State+)
                                  (|>> product.right
-                                      [(///analysis.bundle eval)]))
+                                      [(///analysis.bundle eval host-analysis)]))
                               state)])))
 
-(def: (lux::def expander)
-  (-> Expander Handler)
+(def: (lux::def expander host-analysis)
+  (-> Expander /////analysis.Bundle Handler)
   (function (_ extension-name phase inputsC+)
     (case inputsC+
       (^ (list [_ (#.Identifier ["" short-name])] valueC annotationsC [_ (#.Bit exported?)]))
@@ -160,14 +160,14 @@
          #let [_ (log! (format "Definition " (%name full-name)))]
          _ (/////statement.lift-generation
             (////generation.learn full-name valueN))
-         _ (..refresh expander)]
+         _ (..refresh expander host-analysis)]
         (wrap /////statement.no-requirements))
 
       _
       (////.throw ///.invalid-syntax [extension-name %code inputsC+]))))
 
-(def: (def::type-tagged expander)
-  (-> Expander Handler)
+(def: (def::type-tagged expander host-analysis)
+  (-> Expander /////analysis.Bundle Handler)
   (..custom
    [($_ p.and s.local-identifier s.any s.any (s.tuple (p.some s.text)) s.bit)
     (function (_ extension-name phase [short-name valueC annotationsC tags exported?])
@@ -185,7 +185,7 @@
          #let [_ (log! (format "Definition " (%name full-name)))]
          _ (/////statement.lift-generation
             (////generation.learn full-name valueN))
-         _ (..refresh expander)]
+         _ (..refresh expander host-analysis)]
         (wrap /////statement.no-requirements)))]))
 
 (def: imports
@@ -323,14 +323,14 @@
       _
       (////.throw ///.invalid-syntax [extension-name %code inputsC+]))))
 
-(def: (bundle::def expander program)
+(def: (bundle::def expander host-analysis program)
   (All [anchor expression statement]
-    (-> Expander (-> expression statement) (Bundle anchor expression statement)))
+    (-> Expander /////analysis.Bundle (-> expression statement) (Bundle anchor expression statement)))
   (<| (///bundle.prefix "def")
       (|> ///bundle.empty
           (dictionary.put "module" def::module)
           (dictionary.put "alias" def::alias)
-          (dictionary.put "type tagged" (def::type-tagged expander))
+          (dictionary.put "type tagged" (def::type-tagged expander host-analysis))
           (dictionary.put "analysis" def::analysis)
           (dictionary.put "synthesis" def::synthesis)
           (dictionary.put "generation" def::generation)
@@ -338,10 +338,10 @@
           (dictionary.put "program" (def::program program))
           )))
 
-(def: #export (bundle expander program)
+(def: #export (bundle expander host-analysis program)
   (All [anchor expression statement]
-    (-> Expander (-> expression statement) (Bundle anchor expression statement)))
+    (-> Expander /////analysis.Bundle (-> expression statement) (Bundle anchor expression statement)))
   (<| (///bundle.prefix "lux")
       (|> ///bundle.empty
-          (dictionary.put "def" (lux::def expander))
-          (dictionary.merge (..bundle::def expander program)))))
+          (dictionary.put "def" (lux::def expander host-analysis))
+          (dictionary.merge (..bundle::def expander host-analysis program)))))
diff --git a/stdlib/source/lux/tool/compiler/phase/generation/js/extension.lux b/stdlib/source/lux/tool/compiler/phase/generation/js/extension.lux
index 3bc0a0887..71739bfc9 100644
--- a/stdlib/source/lux/tool/compiler/phase/generation/js/extension.lux
+++ b/stdlib/source/lux/tool/compiler/phase/generation/js/extension.lux
@@ -6,8 +6,10 @@
   [//
    [runtime (#+ Bundle)]]
   [/
-   ["." common]])
+   ["." common]
+   ["." host]])
 
 (def: #export bundle
   Bundle
-  common.bundle)
+  (dictionary.merge common.bundle
+                    host.bundle))
diff --git a/stdlib/source/lux/tool/compiler/phase/generation/js/extension/host.lux b/stdlib/source/lux/tool/compiler/phase/generation/js/extension/host.lux
new file mode 100644
index 000000000..3cf3c6c07
--- /dev/null
+++ b/stdlib/source/lux/tool/compiler/phase/generation/js/extension/host.lux
@@ -0,0 +1,106 @@
+(.module:
+  [lux #*
+   [abstract
+    ["." monad (#+ do)]]
+   [control
+    ["<>" parser
+     ["<s>" synthesis (#+ Parser)]]]
+   [data
+    ["." error]
+    [collection
+     ["." dictionary]]]
+   [target
+    ["_" js (#+ Expression)]]]
+  ["." // #_
+   ["#." common]
+   ["/#" // #_
+    ["#." runtime (#+ Operation Phase Handler Bundle
+                      with-vars)]
+    ["#." primitive]
+    ["/#" // #_
+     [extension (#+ Nullary Unary Binary Trinary
+                    nullary unary binary trinary)]
+     ["/#" //
+      ["." extension
+       ["." bundle]]
+      [//
+       [synthesis (#+ %synthesis)]]]]]])
+
+(def: #export (custom [parser handler])
+  (All [s]
+    (-> [(Parser s)
+         (-> Text Phase s (Operation Expression))]
+        Handler))
+  (function (_ extension-name phase input)
+    (case (<s>.run input parser)
+      (#error.Success input')
+      (handler extension-name phase input')
+
+      (#error.Failure error)
+      (/////.throw extension.invalid-syntax [extension-name %synthesis input]))))
+
+(def: array::new
+  (Unary Expression)
+  (|>> ///runtime.i64//to-number list (_.new (_.var "Array"))))
+
+(def: array::length
+  (Unary Expression)
+  (|>> (_.the "length") ///runtime.i64//from-number))
+
+(def: (array::read [indexG arrayG])
+  (Binary Expression)
+  (_.at indexG arrayG))
+
+(def: (array::write [indexG valueG arrayG])
+  (Trinary Expression)
+  (///runtime.array//write indexG valueG arrayG))
+
+(def: (array::delete [indexG arrayG])
+  (Binary Expression)
+  (///runtime.array//delete indexG arrayG))
+
+(def: array
+  Bundle
+  (<| (bundle.prefix "array")
+      (|> bundle.empty
+          (bundle.install "new" (unary array::new))
+          (bundle.install "length" (unary array::length))
+          (bundle.install "read" (binary array::read))
+          (bundle.install "write" (trinary array::write))
+          (bundle.install "delete" (binary array::delete))
+          )))
+
+(def: js::constant
+  (..custom
+   [<s>.text
+    (function (_ extension phase name)
+      (do /////.monad
+        []
+        (wrap (_.var name))))]))
+
+(def: js::apply
+  (..custom
+   [($_ <>.and <s>.any (<>.some <s>.any))
+    (function (_ extension phase [abstractionS inputsS])
+      (do /////.monad
+        [abstractionG (phase abstractionS)
+         inputsG (monad.map @ phase inputsS)]
+        (wrap (_.apply/* abstractionG inputsG))))]))
+
+(def: js::undefined?
+  (..custom
+   [<s>.any
+    (function (_ extension phase valueS)
+      (|> valueS
+          phase
+          (:: /////.monad map (_.= _.undefined))))]))
+
+(def: #export bundle
+  Bundle
+  (<| (bundle.prefix "js")
+      (|> bundle.empty
+          (bundle.install "constant" js::constant)
+          (bundle.install "apply" js::apply)
+          (bundle.install "undefined?" js::undefined?)
+          (dictionary.merge ..array)
+          )))
diff --git a/stdlib/source/lux/tool/compiler/phase/generation/js/runtime.lux b/stdlib/source/lux/tool/compiler/phase/generation/js/runtime.lux
index 6892879b8..9be09d142 100644
--- a/stdlib/source/lux/tool/compiler/phase/generation/js/runtime.lux
+++ b/stdlib/source/lux/tool/compiler/phase/generation/js/runtime.lux
@@ -696,14 +696,6 @@
       @js//delete
       ))
 
-(runtime: (array//read idx array)
-  (with-vars [temp]
-    ($_ _.then
-        (_.define temp (_.at idx array))
-        (_.if (_.= _.undefined temp)
-          (_.return ..none)
-          (_.return (..some temp))))))
-
 (runtime: (array//write idx value array)
   ($_ _.then
       (_.set (_.at idx array) value)
@@ -717,7 +709,6 @@
 (def: runtime//array
   Statement
   ($_ _.then
-      @array//read
       @array//write
       @array//delete))
 
diff --git a/stdlib/source/program/compositor.lux b/stdlib/source/program/compositor.lux
index 7db076162..506702706 100644
--- a/stdlib/source/program/compositor.lux
+++ b/stdlib/source/program/compositor.lux
@@ -25,6 +25,7 @@
     ["." console]]
    [tool
     [compiler
+     ["." analysis]
      ["." statement]
      ["." phase
       [macro (#+ Expander)]
@@ -78,10 +79,12 @@
       (#error.Failure error)
       (:: io.monad wrap (#error.Failure error)))))
 
-(def: #export (compiler target expander platform generation-bundle host-statement-bundle program service)
+(def: #export (compiler target partial-host-extension expander host-analysis platform generation-bundle host-statement-bundle program service)
   (All [anchor expression statement]
     (-> Text
+        Text
         Expander
+        analysis.Bundle
         (IO (Platform IO anchor expression statement))
         (generation.Bundle anchor expression statement)
         (statement.Bundle anchor expression statement)
@@ -99,12 +102,12 @@
                            {(Platform IO anchor expression statement)
                             platform}
                            {(IO (Error (statement.State+ anchor expression statement)))
-                            (platform.initialize target expander platform generation-bundle host-statement-bundle program)})
+                            (platform.initialize target expander host-analysis platform generation-bundle host-statement-bundle program)})
              [archive state] (:share [anchor expression statement]
                                      {(Platform IO anchor expression statement)
                                       platform}
                                      {(IO (Error [Archive (statement.State+ anchor expression statement)]))
-                                      (platform.compile expander platform configuration archive.empty state)})
+                                      (platform.compile partial-host-extension expander platform configuration archive.empty state)})
              _ (save-artifacts! (get@ #platform.&file-system platform) state)
              ## _ (cache/io.clean target ...)
              ]
diff --git a/stdlib/source/test/lux/tool/compiler/phase/analysis/primitive.lux b/stdlib/source/test/lux/tool/compiler/phase/analysis/primitive.lux
index 8291794d5..2775e1e51 100644
--- a/stdlib/source/test/lux/tool/compiler/phase/analysis/primitive.lux
+++ b/stdlib/source/test/lux/tool/compiler/phase/analysis/primitive.lux
@@ -22,7 +22,8 @@
      ["/#" //
       [macro (#+ Expander)]
       [extension
-       ["#." analysis]]
+       ["#." analysis
+        ["." jvm]]]
       ["/#" //
        ["#." analysis (#+ Analysis Operation)]
        [default
@@ -44,7 +45,8 @@
 
 (def: #export state
   ////analysis.State+
-  [(///analysis.bundle ..eval) (////analysis.state (init.info @.jvm) [])])
+  [(///analysis.bundle ..eval jvm.bundle)
+   (////analysis.state (init.info @.jvm) [])])
 
 (def: #export primitive
   (Random [Type Code])