No macros, limited support for higher order functions. Its big drawback is the small ecosystem.
I like TCL, but its not really comparable to lisp. Its definitely a great scripting language and is a lot more flexible than it gets credit for.
It got a lot of things right. Event driven concurrency (and its got a good threading model) which is often given as a reason to use JS to right servers. Sandboxing untrusted code. Easy GUIs with Tk. Easy cross platform deployment. Unfortunately it never got traction.
Categorically not true. Tcl got a LOT of traction. Expect was everywhere. Tk kicked ass and took names. AOLserver, anyone? VLSI CAD stuff still uses it today.
It just got pushed out of the way over time. IMO, mostly because VB6 took its niche of easy GUI.
