DEBUGGER
========

The DEBUGGER vocabulary implements a set of words that allow any
colon-defined word to be traced.  Words can be stepped into or each
contained word executed in turn. The data and return stacks can also
be inspected and manipulated.

The debugger can be used by first executing

    INCLUDE DEBUGGER.FS

a number of warnings (MSG # 4) will be reported as words that
manipulate the return stack are redefined.


Definitions
-----------

DUMP   ( addr count -- )

    Display the contents of count bytes of memory starting at addr.

TRACE nnnn

    Begin tracing word nnnn. IP is set to the first word and the
    vocabulary is changed to DEBUGGER.

W   ( Where )

    Display the next word.

N   ( Next )

    Display the next word and execute it.

S   ( Step )

    If the next word is a colon-defined word step into it, otherwise
    execute it.

S.  ( Print data stack )

    Print the number of stack items followed by the stack
    contents. The leftmost item is on the top of the stack.

R.  ( Print return stack )

    Print the number of stack items followed by the stack
    contents. The leftmost item is on the top of the stack.
