Represents an Elm type that has been fully resolved:

• all references are now in absolute module format
• type variable applications have been applied
• custom type and type alias information has been added

The constructors are:

• GenericType "foo" ref represents an unfilled type variable foo
• Opaque ref vars represents a custom type (or built in type)
• Function args return represents a function type
• TypeAliasRecord ref args definition represents a record where we have a type alias (and therefore a constructor) available
• AnonymouseRecord extensionVar definition represents an anonymous record
• CustomType ref args [(constructorRef, arguments)] represents a reference to an exposed (or accessible) custom type
• Tuple args represents a tuple.

Let's look at some simple examples and see how they would be represented:

Int --> Opaque { modulePath = ["Basics"], name = "Int" } []


List Int --> Opaque { modulePath = ["Basics"], name = "List" } [Opaque { modulePath = ["Basics"], name = "Int" } []]


List a --> Opaque { modulePath = ["Basics"], name = "List" } [ GenericType "a" Nothing ]


Int -> String  --> Function [ Opaque { modulePath = ["Basics"], name = "Int" } [] ] Opaque { modulePath = ["String"], name = "String" } []


{ foo : Int } --> AnonymousRecord Nothing [ ( "foo",  Opaque { modulePath = ["Basics"], name = "Int" } [] ) ]


{ x | foo : Int } --> AnonymousRecord (Just "x") [ ( "foo",  Opaque { modulePath = ["Basics"], name = "Int" } [] ) ]


() -> Tuple []


( Int, String ) --> Tuple [ Opaque { modulePath = ["Basics"], name = "Int" } [], Opaque { modulePath = ["String"], name = "String" } [] ]

Now for some more complex examples:

type Foo a =
    Bar a


Foo a --> CustomType { modulePath = [], name = "Foo" } [ "a" ] [ ( { modulePath = [], name = "Bar" }, [ GenericType "a" Nothing ] ) ]


Foo Int --> CustomType { modulePath = [], name = "Foo" } [ "a" ] [ ( { modulePath = [], name = "Bar" }, [ GenericType "a" (Just (Opaque { modulePath = ["Basics"], name = "Int" } [] ))] ) ]

Note how in Foo Int the Int value is replaced in the definition.

type alias Qux a =
    { foo : a }


Qux a --> TypeAlias { modulePath = [], name = "Qux" } [ "a" ] [( "foo", GenericType "a" Nothing )]
Qux Int --> TypeAliasRecord { modulePath = [], name = "Qux" } [ "a" ] [( "foo", GenericType "a" (Just (Opaque { modulePath = ["Basics"], name = "Int" } [] )))]

Represents a fully qualified name in Elm source code.