Array#every

class Array
  def every(&block)
    return self unless block_given?
    last = size.nonzero? ? size - 1 : 0
    arity = block.arity
 
    each_with_index { |e, i|
      yield(*[e, i == 0, i == last, i].slice(0, arity)) }
  end
end
 
%w(foo bar).every do |item, is_first, is_last, index|
  # foo => foo, true, false, 0
  # bar => bar, false, true, 1
end
 
# or maybe you don't need 'em all
%w(foo bar).every { |item, first| ... }