Ruby get object keys as array

Question

I am new to Ruby, if I have an object like this

{"apple" => "fruit", "carrot" => "vegetable"} 

How can I return an array of just the keys?

["apple", "carrot"] 

Answer 1

hash = {"apple" => "fruit", "carrot" => "vegetable"} array = hash.keys   #=> ["apple", "carrot"] 

it's that simple

Answer 2

An alternative way if you need something more (besides using the keys method):

hash = {"apple" => "fruit", "carrot" => "vegetable"} array = hash.collect {|key,value| key } 

obviously you would only do that if you want to manipulate the array while retrieving it..