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A Debugger for Tcl Applications



Don E. Libes


Tcl is a language specifically intended for generic application control. By suing it, application programmers escape the dilemma of whether to design sophisticated application-specific languages or whether to build tools more quickly but that are limited in flexibility. Tcl is easy for application programmers to use, however, up to now, there has been no general-purpose debugger for application users.

This paper describes an implementation of a debugger for Tcl applications The debugger has a typical front end but with some extremely unusual commands, in part because of the features and limitations of Tcl. The debugger is modeless, allowing users to issue Tcl and application commands along with debugger commands. Each type of command may invoke the other, allowing debugging to be programmed, dynamically or in advance.

The debugger is written in C and is very fast. When linked in but not used, it does not show applications at all. The debugger requires no modifications to the Tcl core,a nd can be plugged into applications with little effort.

Proceedings Title
Proceedings of the 1993 Tcl/Tk Conference


debugger, Expect, interpreter, Tcl, Tk, Tool Command Language


Libes, D. (1993), A Debugger for Tcl Applications, Proceedings of the 1993 Tcl/Tk Conference (Accessed April 14, 2024)
Created January 1, 1993, Updated February 17, 2017