Retrieving Values from Hashes
In Ruby, there are at least two ways to get a specific value from a hash with two different results if the key is not found.
1. Hash#fetch
h = { "a" => 100, "b" => 200 } h.fetch("z") => KeyError: key not found: "z"from (pry):26:in `fetch'
2. hsh[key] → value
h = { "a" => 100, "b" => 200 } h["z"] => nil
Which one you want to use depends on whether you want to raise an error if it doesn’t exist or just check if it is nil.