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Subject: Re: [Caml-list] destructive local opens

On 17/08/15 16:26, Gabriel Scherer wrote:
> both (let open!)
> and M.!(...) are dangerous constructions that should be avoided
> whenever possible, and that we could and should drastically reduce the
> number of situations where the user is encouraged to use them.

This may have been brought up before, but one way to discourage would be
to make it very verbose. One would require both (let open!) or M.!() at
the shadowing site and an extra annotation for each identifier or
operator in M's signature that is supposed to shadow. The signature
would then have to carry that information around.

Then M.() would never shadow, M.!() indicates possibility of shadowing
and by looking at the type of M one can see which of M's values are
actually shadowing? A tool like merlin could then even annotate this
graphically.

but this may be too drastic a change...

n.