> One LISP system that I have used long ago had a different approach. In it, one closing square bracket could be used to close all non-closed parentheses preced

> One LISP system that I have used long ago had a different approach. In it, one closing square bracket could be used to close all non-closed parentheses preceding it. That was Interlisp, originally making handling of punch cards easier. Nowadays it's not necessary, since the 70s/80s text editors on terminals support handling nested expressions.