Method: Hash#slice

Defined in:
lib/active_support/core_ext/hash/slice.rb

#slice(*keys) ⇒ Object

Slice a hash to include only the given keys. This is useful for limiting an options hash to valid keys before passing to a method:

def search(criteria = {})
  assert_valid_keys(:mass, :velocity, :time)
end

search(options.slice(:mass, :velocity, :time))

If you have an array of keys you want to limit to, you should splat them:

valid_keys = [:mass, :velocity, :time]
search(options.slice(*valid_keys))



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# File 'lib/active_support/core_ext/hash/slice.rb', line 15

def slice(*keys)
  keys = keys.map! { |key| convert_key(key) } if respond_to?(:convert_key)
  hash = self.class.new
  keys.each { |k| hash[k] = self[k] if has_key?(k) }
  hash
end