Tcl hasn't been string based for 20 years, misinformation is hard to eliminate. Since the release of version 8.0 in 2001, Tcl internally has value types for integer, bigints, double, boolean, lists, etc.. As long as you're careful not to cause the internal value to 'shimmer' into a string representation, Tcl maintains the value type as last used. Tcl happily converts values to strings as needed, giving the impression of 'everything is a string'.
