You can actually reference any frame in the stack all the way to the top. And it has a companion "uplevel" which allows you to evaluate code on any of those sta

You can actually reference any frame in the stack all the way to the top. And it has a companion "uplevel" which allows you to evaluate code on any of those stack frames. But usually both are used only with the previous stack frame. This allows TCL functions to mostly behave like macros.