easier Structual typing with dry-types

dry_rb_structural_type.rb

#Types.Interface
#Types.Interface builds a type that checks a value responds to given methods.
#
#Contact = Types.Interface(:name, :phone)
# https://dry-rb.org/gems/dry-types/1.7/custom-types/#code-types-interface-code

require 'dry-types'
require 'dry-struct'

module DryStructalBuilder
  def self.define!(**attrs)
    Class.new(Dry::Struct) do
      class << self
        private
        def flatten_rule(rule)
          if rule.respond_to?(:rules)
            rule.rules
          else
            [rule]
          end
        end
        def all_are_interface?(messages)
          messages.all? do |msg|
            flatten_rule(msg.rule).any? {|rule| rule.predicate.name == :respond_to? }
          end
        end
      end
      attrs.each do |name, message_s|
        ary_messages = [*message_s]
        if ary_messages.all? { _1.is_a?(Symbol) }
          attribute name, Types.Interface(*ary_messages)
        elsif all_are_interface?(ary_messages)
          attribute? name, message_s
        else
          raise Dry::Struct::Error, "Invalid types in messages list #{ary_messages}"
        end
      end    
      def matches?(other)
        attributes.keys.all? { other.respond_to?(_1) }
      end
    end
  end
end

module Types
  include Dry.Types()
end


Car = DryStructalBuilder.define!(model: Types.Interface(:length))
Car.new(model: 'ford')
CarOne = DryStructalBuilder.define!(model: Types.Interface(:length).optional)
CarOne.new(model: nil)
CarOne.new
CarTwo = DryStructalBuilder.define!(model: :length)
CarTwo.new(model: 'ford')
CarThree = DryStructalBuilder.define!(model: [:length, :hash])
CarThree.new(model: 'ford')

need to add not nil attribute :default_role, Types::Interface(:to_s).constrained(not_eql: nil)

only accepts Types.Interface however an interface is just a constrained type with nothing but respond_to? rules
#<Dry::Types[Constrained<Any rule=[respond_to?(:id) AND respond_to?(:name)]>]>