[acveilleux]

Most shell interpreter follow this model, perhaps he started Tcl has an improved shell scripting system and only later improved it? It would explain some of the syntax choices which is fairly reminescent of c-shell and some bourne thrown in.

[normac]

That's pretty much what Tcl is, even to this day. Ousterhout saw scripting languages as extremely high level tools used to issue commands to the low level code that does the heavy lifting. It's very much the same philosophy as shell scripts, except you implement new commands as extensions to Tcl instead of command line programs, and it all runs in the same process.

Of course, the language has matured and now it's also usable for building rich and complex apps top to bottom, just like any modern scripting language.