denisdefreyne

class Employee
  # …
  def hash
    [self.class, @id].hash
  end
end

denisdefreyne

class Path
  # …
  def hash
    [self.class, @components].hash
  end
end

denisdefreyne

class Point
  # …
  def hash
    [self.class, @x, @y].hash
  end
end

denisdefreyne

class Path
  # …
  def ==(other)
    other.respond_to?(:to_str) &&
      to_str == other.to_str
  end

  def eql?(other)
    self.class == other.class &&
      @components == other.components

denisdefreyne

class Employee
  # …
  def ==(other)
    self.eql?(other)
  end
end

denisdefreyne

class Point
  # …
  def ==(other)
    self.eql?(other)
  end
end

denisdefreyne

1 == 1.0        # => true
1.eql?(1.0)     # => false
1.0.eql?(1.0)   # => true

denisdefreyne

"foo" == "foo"      # => true
"foo".eql?("foo")   # => true
"foo".eql?("bar")   # => false

denisdefreyne

class Employee
  # …
  def ==(other)
    self.equal?(other) || (
      # …
    )
  end
end

denisdefreyne

class Employee
  # …
  def ==(other)
    super || (
      self.class == other.class &&
      [email protected]? &&
      @id == other.id
    )
  end
end