Tests / Filters

[sagotch]

Here is a proposal:
Have a special tests collection in context or environment. In the case of a is test, we could look at this collection first, and look for a regular filter if you found nothing.

In this case, we could have something like this

  | TestOpExpr(target, IdentExpr test) -> jg_test env ctx test [value_of_expr env ctx target]
  | TestOpExpr(target, test) -> jg_apply (value_of_expr env ctx test) [value_of_expr env ctx target]

and jg_test env ctx test v =
  try (Hashtbl.find env.tests test) v
  with Not_found -> jg_apply  (jg_get_value ctx test) v

with some std_tests defined in Jg_runtime, but nothing hardcoded in Jg_interp. i.e. user could use its own implementation / add any tests he wants.

[sagotch]

Another option would be to fail if nothing is found in tests (i.e. do not consider it as a regular application).