An interactive shell is easier to prove some simple idea or check a piece of code. Also it is easier to debug or learn certain module without write, save, run.
Actually, a perl -de 1 is a good interactive shell. But I'd rather use a simple, but easier to customize and extend, shell.
The location of interactive shell program. Default is psh.pl. You can change it to “-de 1” if you want it be a debugger or gtksh.pl if you want develop with Gtk2-Perl.
lexcial variable can not live after eval. So when this option turn on, when send one line code to process, the my declaration at beginning of line will be removed. The variable(s) will become global.
For key bindings in cperl-mode, See pde.