name clash when using external types

[ygrek]

consider

type url = string options "ocaml.type" = "Url.t, Url.parse_exn, Url.show"

this will generate module Url with type Url.url = Url.t while the following generated code will reference Url.t directly which is not in scope now because generated Url module hides the external one.

[mfp]

I know this comes two years late, but here it goes for the record:

using a different alias, annoying as it might be, seems a reasonable workaround in this case

type url_ = ...

The ocaml type is "inlined", so that references to url_ in the protocol become Url.t in the generated type definitions. The one remaining annoyance outside the proto is that the generated pp_url_ function includes
the trailing underscore, but these functions are sort of an inner implementation detail anyway, as the user is only supposed to use messages externally.

[ygrek]

yes, this works and that's what I ended up using