Wrong expression type

[giorgix3]

Hi,

While compiling on OSX I get the following:

File "src/lib/usbmux.ml", line 260, characters 9-336:
Error: This expression has type
(Yojson.Safe.json Lazy.t * ([< Error of string |Ok of 'b ] as 'a))
list -> 'b list
but an expression was expected of type
(Yojson.Safe.json Lazy.t *
tunnel Ppx_deriving_yojson_runtime.error_or)
list -> 'c
Type 'a is not compatible with type
tunnel Ppx_deriving_yojson_runtime.error_or =
(tunnel, string) Result.result`

[fxfactorial]

Hi @giorgix3

Was this from opam install usbmux or was it git cloning the repo and then trying to build? Can you do an opam update and then try again? and can you provide various version numbers for stuff? like opam, ocaml, etc.

[giorgix3]

Hi, it was from opam install usbmux

I have the following versions that I installed via MacPort

  ocaml @4.02.2_1 (active)
  ocaml-camlp4 @4.02-6_1 (active)
  opam @1.2.2_0 (active)

Now I ran

  opam update
  opam upgrade
  opam install usbmux

but the same error pops up.

[fxfactorial]

@giorgix3

Okay, it seems that this is a brew created ocaml/opam installation, also the campl4 isn't relevant cause we're using ppx here (Its the replacement for camlp4).

Can you try this sequence:

This will make a separate compiler namespace so to speak and then install usbmux on that switch.

$ opam switch working -A 4.03.0
$ eval `opam config env`
$ opam install usbmux -y

[fxfactorial]

@giorgix3 I think this should be fixed now, try again? Be sure to first do: opam update, then either opam upgrade usbmux or opam install usbmux