Module: Buff::Extensions::Hash::Slice
- Included in:
- Hash
- Defined in:
- lib/buff/extensions/hash/slice.rb
Overview
Borrowd and modified from https://github.com/rails/rails/blob/master/activesupport/lib/active_support/core_ext/hash/slice.rb
Instance Method Summary collapse
-
#extract!(*keys) ⇒ Object
Removes and returns the key/value pairs matching the given keys.
-
#slice(*keys) ⇒ Object
Slice a hash to include only the given keys.
-
#slice!(*keys) ⇒ Object
Replaces the hash with only the given keys.
Instance Method Details
#extract!(*keys) ⇒ Object
Removes and returns the key/value pairs matching the given keys.
{ a: 1, b: 2, c: 3, d: 4 }.extract!(:a, :b) # => {:a=>1, :b=>2}
{ a: 1, b: 2 }.extract!(:a, :x) # => {:a=>1}
41 42 43 |
# File 'lib/buff/extensions/hash/slice.rb', line 41 def extract!(*keys) keys.each_with_object(self.class.new) { |key, result| result[key] = delete(key) if has_key?(key) } end |
#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 = {})
criteria.assert_valid_keys(:mass, :velocity, :time)
end
search(.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(.slice(*valid_keys))
19 20 21 22 |
# File 'lib/buff/extensions/hash/slice.rb', line 19 def slice(*keys) keys.map! { |key| convert_key(key) } if respond_to?(:convert_key, true) keys.each_with_object(self.class.new) { |k, hash| hash[k] = self[k] if has_key?(k) } end |
#slice!(*keys) ⇒ Object
Replaces the hash with only the given keys. Returns a hash containing the removed key/value pairs.
{ a: 1, b: 2, c: 3, d: 4 }.slice!(:a, :b)
# => {:c=>3, :d=>4}
29 30 31 32 33 34 35 |
# File 'lib/buff/extensions/hash/slice.rb', line 29 def slice!(*keys) keys.map! { |key| convert_key(key) } if respond_to?(:convert_key, true) omit = slice(*self.keys - keys) hash = slice(*keys) replace(hash) omit end |