[incr Tcl] is the most widely used O-O system for Tcl. The name is a play on C++, and [incr Tcl] provides a similar object model, including multiple inheritence and public and private classes and variables.
ITCL模拟了C++的面向对象特征,支持单继承和多继承(多态,目前还没有发现有关这方面的资料)。