Method: Linked::List#shift

Defined in:
lib/linked/list.rb

#shift ⇒ Listable?

Shift the first item off the list.

Returns:

  • (Listable, nil) —

    the first item in the list, or nil if the list is empty.



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# File 'lib/linked/list.rb', line 114

def shift
  return nil if empty?

  if list_head.last?
    @_chain.tap { @_chain = nil }
  else
    old_head = list_head
    @_chain = list_head.next
    old_head.delete
  end
end