How do I fetch multiple hash values at once?

What is a shorter version of this?:

from = hash.fetch(:from)
to = hash.fetch(:to)
name = hash.fetch(:name)
# etc

Note the fetch, I want to raise an error if the key doesn't exist.

There must be shorter version of it, like:

from, to, name = hash.fetch(:from, :to, :name) # <-- imaginary won't work

It is OK to use ActiveSupport if required.

Use Hash's values_at method:

from, to, name = hash.values_at(:from, :to, :name)

This will return nil for any keys that don't exist in the hash.

Ruby 2.3 finally introduces the fetch_values method for hashes that straightforwardly achieves this:

{a: 1, b: 2}.fetch_values(:a, :b)
# => [1, 2]
{a: 1, b: 2}.fetch_values(:a, :c)
# => KeyError: key not found: :c

hash = {from: :foo, to: :bar, name: :buz}

[:from, :to, :name].map{|sym| hash.fetch(sym)}
# => [:foo, :bar, :buz]
[:frog, :to, :name].map{|sym| hash.fetch(sym)}
# => KeyError

my_array = {from: 'Jamaica', to: 'St. Martin'}.values_at(:from, :to, :name)
my_array.keys.any? {|key| element.nil?} && raise || my_array

This will raise an error like you requested

 my_array = {from: 'Jamaica', to: 'St. Martin', name: 'George'}.values_at(:from, :to, :name)
 my_array.keys.any? {|key| element.nil?} && raise || my_array

This will return the array.

But OP asked for failing on a missing key...

class MissingKeyError < StandardError
end
my_hash = {from: 'Jamaica', to: 'St. Martin', name: 'George'}
my_array = my_hash.values_at(:from, :to, :name)
my_hash.keys.to_a == [:from, :to, :name] or raise MissingKeyError
my_hash = {from: 'Jamaica', to: 'St. Martin'}
my_array = my_hash.values_at(:from, :to, :name)
my_hash.keys.to_a == [:from, :to, :name] or raise MissingKeyError