class BCDD::Result
  private attr_accessor unknown: bool
  private attr_writer transitions: Hash[Symbol, untyped]
  private attr_reader type_checker: BCDD::Result::Contract::TypeChecker

  attr_reader data: BCDD::Result::Data
  attr_reader subject: untyped
  attr_reader halted: bool
  attr_reader transitions: Hash[Symbol, untyped]

  def self.config: -> BCDD::Result::Config
  def self.configuration: { (BCDD::Result::Config) -> void } -> BCDD::Result::Config

  def initialize: (
    type: Symbol,
    value: untyped,
    ?subject: untyped,
    ?expectations: BCDD::Result::Contract::Evaluator,
    ?halted: bool
  ) -> void

  def type: -> Symbol
  def value: -> untyped

  def halted?: -> bool
  def success?: (?Symbol type) -> bool
  def failure?: (?Symbol type) -> bool

  def value_or: { () -> untyped } -> untyped

  def on: (*Symbol) { (untyped, Symbol) -> void } -> BCDD::Result
  def on_success: (*Symbol) { (untyped, Symbol) -> void } -> BCDD::Result
  def on_failure: (*Symbol) { (untyped, Symbol) -> void } -> BCDD::Result
  def on_unknown: () { (untyped, Symbol) -> void } -> BCDD::Result

  def and_then: (?Symbol method_name, ?untyped context) ?{ (untyped) -> untyped } -> untyped

  def handle: () { (BCDD::Result::Handler) -> void } -> untyped

  def ==: (untyped) -> bool
  def hash: -> Integer
  def inspect: -> String

  def deconstruct: -> [Symbol, [Symbol, untyped]]
  def deconstruct_keys: (Array[Symbol]) -> Hash[Symbol, Hash[Symbol, untyped]]

  alias eql? ==
  alias on_type on

  private

  def kind: -> Symbol
  def known: (Proc) -> untyped
  def call_and_then_subject_method: (Symbol, untyped) -> BCDD::Result
  def call_and_then_subject_method!: (untyped, untyped) -> BCDD::Result
  def call_and_then_block: (untyped) -> BCDD::Result
  def call_and_then_block!: (untyped) -> BCDD::Result
  def ensure_result_object: (untyped, origin: Symbol) -> BCDD::Result
end

class BCDD::Result
  class Success < BCDD::Result
    module Methods
      def success?: (?Symbol type) -> bool
      def failure?: (?Symbol type) -> bool
      def value_or: { () -> untyped } -> untyped
      def value: -> untyped

      private

      def kind: -> Symbol
      def type_checker: -> BCDD::Result::Contract::TypeChecker
    end

    include Methods
  end

  def self.Failure: (Symbol type, ?untyped value) -> BCDD::Result::Failure
end

class BCDD::Result
  class Failure < BCDD::Result
    module Methods
      def success?: (?Symbol type) -> bool
      def failure?: (?Symbol type) -> bool
      def value_or: { (untyped) -> untyped } -> untyped
      def value: -> untyped

      private

      def kind: -> Symbol
      def type_checker: -> BCDD::Result::Contract::TypeChecker
    end

    include Methods
  end

  def self.Success: (Symbol type, ?untyped value) -> BCDD::Result::Success
end