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===== Log of Changes checked in by user ram on Fri Jul 10 17:34:05 1992
File: debug.lisp
Exported variables *use-block-starts-only* and *print-code-location-kind*
which control the verbosity of LIST-LOCATIONS.
Imroved source file organization.
Changed PRINT-FRAME-CALL to print the source if verbosity >= 2 and
the source is available.
Removed mentions of *current-code-location*, which was only set, never read.
Changed source location printing to cache information so that it is much
faster when many locations in the same function are printed.
The source file is now only printed when the file changes from one 
printing to the next.
The format of LIST-LOCATIONS is now more readable.  The number: comes before
the form, and consecutive locations with the same souce print as ranges,
not as multiple lines.
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===== Log of Changes checked in by user ram on Mon Aug  3 13:55:23 1992
File: debug.lisp
Fixed VPRINT command to actually be verbose.
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===== Log of Changes checked in by user ram on Tue Jul 20 10:59:53 1993
File: error.lisp
Bind *break-on-signals* to NIL when we call BREAK in SIGNAL so that
the debugger doesn't recurse on itself.
..
