These days we also have psysh.org which is a pretty sweet interactive PHP shell. Doesn't have the sophisticated halting and rewinding and redefining that Commo

These days we also have psysh.org which is a pretty sweet interactive PHP shell. Doesn't have the sophisticated halting and rewinding and redefining that Common Lisp and other image based REPL:s do, but it allows for very rapid development in a similar way.