Edit: If this subthread got you interested, antirez's other Tcl projects are worth checking out. They are listed on his page on the Tcler's wiki: https://tcl.wiki/9497. I particularly recommend https://tcl.wiki/Picol, the tiny predecessor to Jim Tcl, and https://tcl.wiki/Sugar, a macro system for Tcl 8.4+. Disclosure: I maintain a somewhat larger fork of the former.
Jim Tcl sounds really awesome. I use tcl quite a bit as the embedded scripting language in a CAE app. Things like OO with garbage collection and closures/functional primitives are probably what I miss the most from Tcl.
Edit: If this subthread got you interested, antirez's other Tcl projects are worth checking out. They are listed on his page on the Tcler's wiki: https://tcl.wiki/9497. I particularly recommend https://tcl.wiki/Picol, the tiny predecessor to Jim Tcl, and https://tcl.wiki/Sugar, a macro system for Tcl 8.4+. Disclosure: I maintain a somewhat larger fork of the former.