1 files changed, 40 insertions, 0 deletions
diff --git a/hash.rb b/hash.rb
new file mode 100644
index 0000000000..99b34a9bda
--- /dev/null
+++ b/hash.rb
@@ -0,0 +1,40 @@
+class Hash
+  # call-seq:
+  #   Hash.new(default_value = nil, capacity: 0) -> new_hash
+  #   Hash.new(capacity: 0) {|self, key| ... } -> new_hash
+  #
+  # Returns a new empty \Hash object.
+  #
+  # Initializes the values of Hash#default and Hash#default_proc,
+  # which determine the behavior when a given key is not found;
+  # see {Key Not Found?}[rdoc-ref:Hash@Key+Not+Found-3F].
+  #
+  # By default, a hash has +nil+ values for both +default+ and +default_proc+:
+  #
+  #   h = Hash.new        # => {}
+  #   h.default           # => nil
+  #   h.default_proc      # => nil
+  #
+  # With argument +default_value+ given, sets the +default+ value for the hash:
+  #
+  #   h = Hash.new(false) # => {}
+  #   h.default           # => false
+  #   h.default_proc      # => nil
+  #
+  # With a block given, sets the +default_proc+ value:
+  #
+  #   h = Hash.new {|hash, key| "Hash #{hash}: Default value for #{key}" }
+  #   h.default      # => nil
+  #   h.default_proc # => #<Proc:0x00000289b6fa7048 (irb):185>
+  #   h[:nosuch]     # => "Hash {}: Default value for nosuch"
+  #
+  # Raises ArgumentError if both +default_value+ and a block are given.
+  #
+  # If optional keyword argument +capacity+ is given with a positive integer value +n+,
+  # initializes the hash with enough capacity to accommodate +n+ entries without resizing.
+  #
+  # See also {Methods for Creating a Hash}[rdoc-ref:Hash@Methods+for+Creating+a+Hash].
+  def initialize(ifnone = (ifnone_unset = true), capacity: 0, &block)
+    Primitive.rb_hash_init(capacity, ifnone_unset, ifnone, block)
+  end
+end