is a predicate for applications which consist only of Tcl code (no C extensions or packages).
PRO:
CON:
In general, it is sensible to start coding an app in pure Tcl, and replace only those parts (if any) with C code that are just too slow. (But CPUs are picking up speed considerably faster than C coders ;-) (RS)
There are several subtleties and even polysemies to this term. Sometimes we say, "pure Tcl" in contrast to Tk; thus the 2.0 version of sockspy is useful for certain contexts because it can be run as "pure Tcl" without the requirement for a Tk interpreter.