Issue #6367 has been updated by edtsech (Edward Tsech). I don't know, but I was a little bit confused by that: =begin assert_equal(true, [1,3,9,7].same?(&:even?)) assert_equal(true, [4,8,2,2].same?(&:even?)) =end or I can write smth like that: =begin assert_equal(true, [1.0,2.0,3.0,4.0].same?(&:integer?)) =end Maybe it's just unusable for "primitive" types, because as i understand this method useful for test if all objects in enumerable have the same "property", and "primitive" types actually don't have them. But I like this idea: =begin assert_equal(true, %w{cat dog rat}.same?(&:length)) assert_equal(false, %w{cat dog rabbit}.same?(&:length)) =end ---------------------------------------- Feature #6367: #same? for Enumerable https://bugs.ruby-lang.org/issues/6367#change-26282 Author: prijutme4ty (Ilya Vorontsov) Status: Feedback Priority: Normal Assignee: matz (Yukihiro Matsumoto) Category: Target version: I realised that I frequently test if all objects in enumerable have the same feature. For example if all words have the same length (but not defined before). So I found particulary useful method Enumerable#same_by? that test this behaviour. I think it can be simply rewritten in C and included to Enumerable core methods. Simple ruby implementation can be written just in a pair of lines (tests included): module Enumerable def same?(&block) return true if empty? if block_given? first_result = yield(first) all?{|el| first_result == yield(el)} else first_result = first all?{|el| first_result == el} end end end require 'test/unit' class TestEnumerableSame < Test::Unit::TestCase def test_same assert_equal(true, [1,3,9,7].same?(&:even?)) assert_equal(true, [4,8,2,2].same?(&:even?)) assert_equal(false, [1,8,3,2].same?(&:even?)) assert_equal(true, %w{cat dog rat}.same?(&:length)) assert_equal(false, %w{cat dog rabbit}.same?(&:length)) assert_equal(true, %w{cat cat cat}.same?) assert_equal(false, %w{cat dog rat}.same?) assert_equal(true, [].same?(&:length)) assert_equal(true, [].same?) end end -- http://bugs.ruby-lang.org/