Extended Tcl (TclX) - development package

 Extended Tcl (TclX), is a set of extensions to Tcl, the Tool Command
 Language invented by Dr. John Ousterhout. Tcl is a powerful, yet simple
 embeddable programming language. Extended Tcl is oriented towards system
 programming tasks and large application development.
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 TclX provides additional interfaces to the operating system, and adds many
 new programming constructs, text manipulation tools, and debugging tools.
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 This package includes development libraries and include files.