What's the way to check if all the elements in an array are nil? [duplicate]

Question

I would like to know if there's anything except nil values in an array.

arr = [nil, nil, nil, nil] # => true
arr = [nil, 45, nil, nil] # => false

There could be any values of any types (not only 45).

Answer 1

Use the Enumerable#all? method:

p arr.all? { |x| x.nil? }

Or

p arr.all?(&:nil?)

As @Stefan suggested,

 p arr.all?(NilClass) #works only for Ruby 2.5

Answer 2

you could do arr.compact.empty?, compact gets rid of all the nil for you

you could read here at ruby guides to find about all the methods on Array class