module Ersatz.Types

type Symbol = {
    Module : Module
    Identifier : string
}

and Module = {
    Name : string list
    Definitions : (Symbol * Type * Expression) list
    Imports : Module list
}

and Kind =
    | Star
    | Kinds of Kind list

and PrimitiveType =
    | Integer
    | Float
    | Tuple of Types
    | Array of int * Type
    | List of Type
    | Function of Types

and Qualifier =
    | Mutable
    | Private
    | Internal
and Qualifiers = Qualifier list

and Type' =
    | TypeVariable of Symbol
    | SumType of Types
    | RecordType of (string, Type) Map
    | Primitive of PrimitiveType
    | TypeClass of (Symbol * Types) list

and TypeConstraint = (Symbol * Type) list

and Type = Type' * Kind * TypeConstraint

and Types = Type list

and Binding = {
    Variable : Symbol
    Counter : uint64
    Qualifiers : Qualifiers
}

and Expression =
    | Progn of Expression list
    | Apply of Expression * Expression
    | Lambda of Binding * Expression
    | If of Expression * Expression * Expression
    | Datum of PrimitiveType