ruby/lib/rubygems/util/list.rb

38 строки
584 B
Ruby

# frozen_string_literal: true
module Gem
class List
include Enumerable
attr_accessor :value, :tail
def initialize(value = nil, tail = nil)
@value = value
@tail = tail
end
def each
n = self
while n
yield n.value
n = n.tail
end
end
def to_a
super.reverse
end
def prepend(value)
List.new value, self
end
def pretty_print q # :nodoc:
q.pp to_a
end
def self.prepend(list, value)
return List.new(value) unless list
List.new value, list
end
end
end