How to Remove an Element From an Empty Array in Ruby

An array is like a variable that stores multiple values, rather than one. Arrays can contain a mixture of elements; for example, "a = [1, 'two', 3.0]" is just as valid as "a = [1, 2, 3]". An empty array is an array that contains no elements, such as "a = [ ]". Ruby has two methods you can utilize to create an empty array; one method removes all of the elements from an array at once, while the other removes a single element from the array.

Instructions

1. Input "array.empty?" to check if the array contains elements. If the program returns "true," the array contains no elements to remove.

2. Insert "arrayname.clear" into the code or into Interactive Ruby (IRB) to remove all elements from an array. Replace "arrayname" with the name of the desired array.

3. Insert "a.delete_at(#)" to remove a single element from an array. Ruby starts at "0" when numbering elements in an array. For example,

   a = [1, 2, 3]
   a.delete_at(0)

   the above code would remove "1" from the array, changing the array to "a = [2, 3]". Using "a.delete_at(0)" a second time would remove "2" from the array.

4. Repeat step three until all elements are removed, creating an empty array. You can create a simple loop statement in the program to remove all arrays if you don't want to use the "clear" method:

   while a.empty? == false
   a.delete_at(0)
   end

References

• Ruby: Visual Quickstart Guide; Larry Ullman; 2008
• Ruby-Doc.org: Class: Array