Perl did time-travelling variables first, namely in 2007: Positronic::Variables https://www.flickr.com/photos/gunnarwolf/1343377956/ https://www.flickr.com/pho

Perl did time-travelling variables first, namely in 2007: Positronic::Variables https://www.flickr.com/photos/gunnarwolf/1343377956/ https://www.flickr.com/photos/gunnarwolf/1343377956/ This in the picture is Conway giving the talk.