Ruby: Easiest Way to Filter Hash Keys?

Question

I have a hash that looks something like this:

params = { :irrelevant => \"A String\",
           :choice1 => \"Oh look, another one\",
           :choi         


        

Answer 1

If you work with rails and you have the keys in a separate list, you can use the * notation:

keys = [:foo, :bar]
hash1 = {foo: 1, bar:2, baz: 3}
hash2 = hash1.slice(*keys)
=> {foo: 1, bar:2}

As other answers stated, you can also use slice! to modify the hash in place (and return the erased key/values).