js: remove automatic function -> closure conversion

It's a bad idea for several reasons:

* it's inefficient; must allocate an environment for a closure in Nim,
  even though we already have one in JS
* writing macros for automatically creating functions with variadic
  arguments is suprisingly difficult (see the entire `js/javascript'
  module)
* it never really worked properly, because we never freed the associated
  function pointer.

We hardly used it anyway, so the easiest fix is to get rid of it
completely.

1 files changed, 8 insertions, 0 deletions

diff --git a/src/js/jstypes.nim b/src/js/jstypes.nim
index 5336f067..9e1d72ea 100644
--- a/src/js/jstypes.nim
+++ b/src/js/jstypes.nim
@@ -33,3 +33,11 @@ type
 
 func high*(abuf: JSArrayBuffer): int =
   return int(abuf.len) - 1
+
+# A specialization of JSValue to make writing generic code for functions
+# easier.
+type JSValueFunction* = ref object
+  fun*: JSValue
+
+converter toJSValue*(f: JSValueFunction): JSValue =
+  f.fun