For Ruby: - Enumerator are documented as soon as 1.9.1[1] in 2009[2] - Enumerable are already present in 1.8.6[3] released in 2006[4], and the matching source

For Ruby: - Enumerator are documented as soon as 1.9.1[1] in 2009[2] - Enumerable are already present in 1.8.6[3] released in 2006[4], and the matching source code is easily trackable on Github through enumerable.c[5] back to 2005. The Git repository won’t bring any meaningful information before that on this file, due to the import from SVN if I well understand. There is also an enum.c file, but I’m not versed enough in Ruby code base to tell what is it about. [1] https://ruby-doc.org/core-1.9.1/Enumerator.html https://ruby-doc.org/core-1.9.1/Enumerator.html [2] https://www.ruby-lang.org/en/news/2009/01/30/ruby-1-9-1-released/ https://www.ruby-lang.org/en/news/2009/01/30/ruby-1-9-1-rele... [3] https://ruby-doc.org/core-1.8.6/Enumerable.html https://ruby-doc.org/core-1.8.6/Enumerable.html [4] https://www.ruby-lang.org/en/news/2007/03/12/ruby-1-8-6-released/ https://www.ruby-lang.org/en/news/2007/03/12/ruby-1-8-6-rele... [5] https://github.com/ruby/ruby/commits/master?after=78425d7e74887b57ee15e6b8933bd3878db6a888+314&branch=master&path%5B%5D=enumerator.c&qualified_name=refs%2Fheads%2Fmaster https://github.com/ruby/ruby/commits/master?after=78425d7e74...