The Debugger
============

The debugger tool is a graphic front end for the
LISP debugger. It becomes visible, when a runtime
error occured, to enable the user entering debugging
commands.

Via this tool the programmer is able entering LISP 
commands manually.

It consists of three windows. In the lower window 
commands can be entered, which will be buffered in
the middle window, until LISP reads them for evalu-
ation. 

The evaluation of a command may be interrupted via
the "Break!" button. Additionally a "Clear" button
is available to erase the contents of the output
window. Hence the history is not limited in length,
very large histories may make execution slow!