each

        # Enumerator.each

(from ruby core)
---
    enum.each { |elm| block }                    -> obj
    enum.each                                    -> enum
    enum.each(*appending_args) { |elm| block }   -> obj
    enum.each(*appending_args)                   -> an_enumerator

---

Iterates over the block according to how this Enumerator was
constructed. If no block and no arguments are given, returns self.

### Examples

    "Hello, world!".scan(/\w+/)                     #=> ["Hello", "world"]
    "Hello, world!".to_enum(:scan, /\w+/).to_a      #=> ["Hello", "world"]
    "Hello, world!".to_enum(:scan).each(/\w+/).to_a #=> ["Hello", "world"]

    obj = Object.new

    def obj.each_arg(a, b=:b, *rest)
      yield a
      yield b
      yield rest
      :method_returned
    end

    enum = obj.to_enum :each_arg, :a, :x

    enum.each.to_a                  #=> [:a, :x, []]
    enum.each.equal?(enum)          #=> true
    enum.each { |elm| elm }         #=> :method_returned

    enum.each(:y, :z).to_a          #=> [:a, :x, [:y, :z]]
    enum.each(:y, :z).equal?(enum)  #=> false
    enum.each(:y, :z) { |elm| elm } #=> :method_returned