Module ActiveSupport::CoreExtensions::Hash::Slice
In: lib/active_support/core_ext/hash/slice.rb

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))

Methods

slice   slice!  

Public Instance methods

Returns a new hash with only the given keys.

Replaces the hash with only the given keys. Returns a hash contained the removed key/value pairs

  {:a => 1, :b => 2, :c => 3, :d => 4}.slice!(:a, :b) # => {:c => 3, :d =>4}

[Validate]