The same can be told of the REPL environments of Smalltalk, Interlisp-D, Lisp Machines, Mesa&#x2F;Cedar and Oberon.<p>All more powerful than UNIX shell languages while using structured data.<p>Coming from Spectrum, MS-DOS and Amiga, the UNIX shell seemed powerful until I discovered how the development workstation should look like, from the eyes of Xerox PARC.