ruby array checking for nil array
arrays, null, ruby
Solution
`[""]` is an array with a single element containing an empty String object. `[].empty?` will return `true`. `@a.nil?` is returning `false` because `@a` is an Array object, not `nil`.
Examples:
"".nil? # => false
[].nil? # => false
[""].empty? # => false
[].empty? # => true
[""].all? {|x| x.nil?} # => false
[].all? {|x| x.nil?} # => true
[].all? {|x| x.is_a? Float} # => true
# An even more Rubyish solution
[].all? &:nil? # => true
That last line demonstrates that `[].all?` will always return true, because if an Array is empty then by definition all of its elements (no elements) fulfill every condition.
Problem
I have ruby array and it is `nil` but when I check using `nil?` and `blank?` it returns `false` ``` @a = [""] @a.nil? => false @a.empty? => false ``` How do I check for the nil condition that return true?