merge revision(s) 57584: [Backport #13202]
[DOC] Update an obsolete example for slice_before. The argument for Enumerable#slice_before is is removed at Ruby 2.3. Reported by Shyouhei Urabe. [Bug #13202]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@57905 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merge revision(s) 57584: [Backport #13202]
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@57905 b2dd03c8-39d4-4d8f-98ff-823fe69b080e