Ruby Linked List implementation

Question

I've made a Ruby linked list data structure class and a lookup method. I know that lookup will only fetch the first occurrence and I'm ok with that.

Is it a bad implementation? Why is it bad? What can I improve to make it more idiomatic?

# linear collection of data elements, in which linear order is not given by
# their physical placement in memory. Instead, each element points to the next.
class LinkedList
  attr_accessor :value, :next

  def lookup(lookup_value)
    return self if value.eql? lookup_value
    return self.next.lookup(lookup_value) unless self.next.nil?
  end
end

Test code

root = LinkedList.new
root.value = 5

node1 = LinkedList.new
node1.value = 10

node2 = LinkedList.new
node2.value = 15

node3 = LinkedList.new
node3.value = 12

root.next = node1
node1.next = node2
node2.next = node3

p root.lookup(2) # nil
p root.lookup(15) # #<LinkedList:0x007f83db0a95b8 @value=15, @next=#<LinkedList:0x007f83db0a9590 @value=12>>
p root.lookup(12) # #<LinkedList:0x007fcbe91196a0 @value=12>

Answer 1

Looks pretty good to me. You don't need the explicit return as the last statement of your lookup method. Also, in newer versions of Ruby (2.3+ I believe), you don't need the explicit nil check--instead, you can use the Safe Navigation Operator (&.).

  def lookup(lookup_value)
    return self if value.eql? lookup_value
    self.next&.lookup(lookup_value)
  end