Ruby nil? Empty? Blank? Difference

Sky = nilsky. nil? #=> True
All other objects are object. nil? All are false. If a database attribute is null, the attribute is. nil? #=> True

Empty? Used for string, array, and hash

# Array []. Empty? #=> True # string "". Empty? #=> True
But "". Empty? #=> False

 Blank?Object Class

"", Nil, [], and {}. Blank? #=> True

This simplifies

If! Address. nil? &&! Address. Empty?

To

If! Address. Blank?

Seemingly blank? Is it nil? And empty? But there is still a difference: "". Empty? #=> False, "". Blank #=> true

. Nil?