Re: [Caml-list] ANN: improved BER MetaOCaml N101, for OCaml 4.01

[Gabriel Kerneis <gabriel@kerneis.info>]

Hi Oleg,

On Wed, Nov 27, 2013 at 07:30:30AM -0000, oleg@okmij.org wrote:
> The scope extrusion check first introduced in BER N100 made it
> possible to remove environment classifiers while still preserving the
> static guarantee: if the generator finishes successfully, the
> generated code is well-typed and well-scoped. Environment classifiers
> ensured well-scopedness when type-checking the generator -- but only
> for pure generators. The scope extrusion check is executed when the
> generator is run; however the check is comprehensive. Scope extrusion
> is always caught, and caught early, whether the generator is effectful
> or not.

I'm not sure I understand correctly the difference between open and close code,
and what is the challenge with effects.  Could you please give examples of:
(1) a pure generator for well-typed, well-scoped open code,
(2) a pure generator for well-typed, ill-scoped open code,
(3) an effectful generator for well-typed, ill-scoped open code.

I assume (2) would be caught statically by BER N100, and (3) dynamically by BER
N101. But what would happen for (2) with BER N100?

Many thanks,
-- 
Gabriel