The Inline::Tcl module allows you to put Tcl source code directly
"inline" in a Perl script or module. A Tcl interpreter is loaded and the
Tcl code is interpreted, then Perl asks the Tcl interpreter which global
procedures have been defined. Those functions are made available to your
Perl program as if they had been written in Perl.

The process of interrogating the Tcl interpreter for globals only occurs
the first time you run your Tcl code. The namespace is cached, and
subsequent calls use the cached version.