[0.16-alpha] Can't find generated function for extensible record

[Warry]

I don't know if this is because of my cranky environment (elm-lang/elm-repl#80), but I can't compile code using generated functions for the extensible records:

The error:

➜ elm-make Main.elm
[                                                  ] - 0 / 1
elm-make: Could not find `Foo` when solving type constraints.
elm-make: thread blocked indefinitely in an MVar operation

The sample:

type alias Foo a =
  { a | foo : String }

-- Code that breaks (each with the same error):

myFoo : Foo {}
myFoo = Foo "Hello" {}

myFoo2 : Foo { x : Int }
myFoo2 = Foo "Hello" { x = 42 }

myFoo3 : a -> Foo a
myFoo3 x = Foo "Hello" x

--

-- All the following works:

type alias Bar a =
  { a | bar : String }

myBar : Bar {}
myBar = { bar = "World!" }

type alias Baz =
  { baz : String }

myBaz : Baz
myBaz = Baz "John"

Env. : 0.16-alpha on osX 10.11
The same code works on 0.15.1

[Warry]

Maybe related to #953

[evancz]

Records with type holes no longer generate record constructors. So there should be no Foo function for creating values in the first place. Record extension literally does not exist in syntax anymore, and this is one form of it.

[Warry]

Ok, I'll make a PR for the update to 0.16 docs

[evancz]

The weird thing is that this is not a NAMING ERROR, where it cannot find Foo at the value level. I don't quite get that, and it seems like a bug.

[Warry]

Ok, feel free to reopen the issue if you think it's relevant.

[ccapndave]

elm/error-message-catalog#67