'''Backtracking and Constraints in Tcl-BC''' at USENIX Fourth Annual Tcl/Tk Workshop
Monterey, California, July 1996

 Dayton Clark and David M. Arnow
 Dept. of Computer and Information Science
 Brooklyn College
 {dayton,arnow} @sci.brooklyn.cuny.edu
ABSTRACT: Tcl is extended to include backtracking controls and a facility for asserting constraints. This increases its flexibility in several domains and opens the possibility for its use in constraint-based logic programming applications and, conversely, applying constraint-based logic programming techniques to more traditional script language domains. The backtracking extensions are written entirely in Tcl itself, a fact which speaks well for Tcl's own extensibility. 

Full paper at [http://www.usenix.org/publications/library/proceedings/tcl96/full_papers/clark/index.html]

Source code bc.tcl (.tar.gz) at [http://mini.net/files/tcl-bc.tar.gz]

George Petasis: An updated version of bc.tcl which runs under Tcl 8.4 can be found at:
Page: [http://www.ellogon.org/petasis/index.php?option=com_docman&task=cat_view&gid=21&Itemid=37]
bc.tcl: [http://www.ellogon.org/petasis/index.php?option=com_docman&task=doc_download&gid=56&Itemid=37]