Older APL programs used a 2D layout to show control flow, which probably worked well in handwriting but not so well once APL started being used as a programming

Older APL programs used a 2D layout to show control flow, which probably worked well in handwriting but not so well once APL started being used as a programming language, rather than as a notation for specifying a program to be written. This page has some examples: http://www.zerobugsandprogramfaster.net/essays/5b.html http://www.zerobugsandprogramfaster.net/essays/5b.html