Comment by jdblair

Lua fits the same niche as Tcl, but the runtime is smaller and way better. Tcl started as a simple, embeddable scripting language (and low performance, it was just string substitutions!) and evolved into Tcl8, a mostly backward compatible object system after successive iterations to improve its performance and expressiveness. "everything is a table" gets you pretty far in Lua, in much the same way that "everything is a list" in lisp, and was a much better abstraction than Tcl's "everything is a string."

When I last used Lua professionally (10 years ago) I did discover some foot-guns related to the handling of NULL / nil in the LuaSQL module. The Lua array length function was based on nil-termination, so a NULL value in a column could cause issues. Maybe this has been fixed by now?