From 76977611dd68e384fdce8c546efda5e1931e67a6 Mon Sep 17 00:00:00 2001 From: knu Date: Sat, 5 Nov 2016 09:23:14 +0000 Subject: Add Set#compare_by_identity and Set#compare_by_identity? * lib/set.rb (Set#compare_by_identity, Set#compare_by_identity?): New methods. [Feature #12210] git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@56589 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- lib/set.rb | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) (limited to 'lib/set.rb') diff --git a/lib/set.rb b/lib/set.rb index e77af5de2e..43c388ca90 100644 --- a/lib/set.rb +++ b/lib/set.rb @@ -3,7 +3,7 @@ # # set.rb - defines the Set class #++ -# Copyright (c) 2002-2013 Akinori MUSHA +# Copyright (c) 2002-2016 Akinori MUSHA # # Documentation by Akinori MUSHA and Gavin Sinclair. # @@ -37,7 +37,8 @@ # Set uses Hash as storage, so you must note the following points: # # * Equality of elements is determined according to Object#eql? and -# Object#hash. +# Object#hash. Use Set#compare_by_identity to make a set compare +# its elements by their identity. # * Set assumes that the identity of each element does not change # while it is stored. Modifying an element of a set will render the # set to an unreliable state. @@ -91,6 +92,23 @@ class Set end end + # Makes the set compare its elements by their identity and returns + # self. This method may not be supported by all subclasses of Set. + def compare_by_identity + if @hash.respond_to?(:compare_by_identity) + @hash.compare_by_identity + self + else + raise NotImplementedError, "#{self.class.name}\##{__method__} is not implemented" + end + end + + # Returns true if the set will compare its elements by their + # identity. Also see Set#compare_by_identity. + def compare_by_identity? + @hash.respond_to?(:compare_by_identity?) && @hash.compare_by_identity? + end + def do_with_enum(enum, &block) # :nodoc: if enum.respond_to?(:each_entry) enum.each_entry(&block) if block -- cgit v1.2.3