ruby slice with array cirteria

Question

How can I create an slice for a hash in ruby looking by an array, like this:

info         = { :key1 => "Lorem", :key2 => "something...", :key3 => "Ipsum" }
needed_keys  = [:key1, :key3]
info         = info.slice( needed_keys )

I want to receive:

{ :key1 => "Lorem", :key3 => "Ipsum" }

Answer 1

ActiveSupport's Hash#slice doesn't take an array of keys as argument, you have to pass the keys you want to extract as single arguments, for example by splatting your needed_keys array:

info.slice(:key1, :key3)
# => {:key1=>"Lorem", :key3=>"Ipsum"}

info.slice(*needed_keys)
# => {:key1=>"Lorem", :key3=>"Ipsum"}