class Plumb::MatchClass

def _inspect = @label

def build_error(matcher)
  case matcher
  when Class # A class primitive, ex. String, Integer, etc.
    "Must be a #{matcher}"
  when ::String, ::Symbol, ::Numeric, ::TrueClass, ::FalseClass, ::NilClass, ::Array, ::Hash
    "Must be equal to #{matcher}"
  when ::Range
    "Must be within #{matcher}"
  else
    "Must match #{matcher.inspect}"
  end
end

def call(result)
  @matcher === result.value ? result : result.invalid(errors: @error)
end

def initialize(matcher = Undefined, error: nil, label: nil)
  raise ParseError 'matcher must respond to #===' unless matcher.respond_to?(:===)
  @matcher = matcher
  @error = error.nil? ? build_error(matcher) : (error % matcher)
  @label = matcher.is_a?(Class) ? matcher.inspect : "Match(#{label || @matcher.inspect})"
  @children = [matcher].freeze
  freeze
end