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Ruby Ruby Collections Ruby Arrays Removing Items From Arrays

Kody Ellis
Kody Ellis
2,098 Points

Why can't I delete more than 1 thing in a Ruby array using .delete_at?

Why can't you pass more than 1 argument using the delete_at method???Even the official documentation is unclear on this.

Actual delete method will delete an array item based on actual name

grocery_list = ["0apple", "1apple", "2apple", "3apple", "4apple", "5apple",]
grocery_list.delete("0apple")

Delete_at method deletes an item based on its index number

#prints out: ["1apple", "2apple", "3apple", "4apple", "5apple",]
grocery_list.unshift "0apple"
grocery_list.delete_at(1)

However, when I tell it to delete more than 1 thing, it says error

#prints out: ["0apple", "2apple", "3apple", "4apple", "5apple",]
grocery_list.insert(1,"1apple")
grocery_list.delete_at(1,2)

I should get this

["0apple", "3apple", "4apple", "5apple",]

But, I get an error message like this:

rb:11 :in `delete_at': wrong number of arguments (2 for 1) (ArgumentError)
from C:/Users/mildr_000/rubyhotspot2.rb:11:in ' main '

If delete_at doesn't work, how else can I delete multiple items in the array based on index number?(without using a loop)

1 Answer

dan parker
dan parker
9,843 Points

Delete_at(index) Deletes the element at the specified index, returning that element, or nil if the index is out of range. From the Docs.

It accepts only one argument. You can only delete at one index, the return is the deleted item, and the original object is modified.

Try slice, take, take_while, drop, delete_if there is an option depending on you goal.

http://ruby-doc.org/core-2.2.0/Array.html