Tcl still is in use in a number of environments like embedded devices. However, looking at Tcl code fragments reminded me of why I gave up on Tcl many years ago. I can't really recommend spending much time in Tcl.
However, if Tcl is your only choice for "primary information", then you need to translate the information from a Tcl structure into another format. Potential candidates for this are XML, JSON, or YAML. I think JSON is a little better for most simple data structures you may find in Tcl, but pick your poison.