8/30/71   - JONL - 

OH, HAPPY DAY!
LISP WILL NO LONGER GO AWAY
WHEN THE GARBAGE COLLECTOR UNDERFLOWETH.

INTERRUPT NUMBER TEN
WILL CATCH AS CATCH CAN
A LESS-THAN-MINIMAL AMOUNT OF STORETH.

(SSTATUS GCMIN '(MINFS
MINFXS MINFLS))
RESETS THE DEFAULT RATE

WICH COMES TO YOU
IN A LISP NEW
AT 100, 20, AND EIGHT.



A STATUS CALL CORRESPONDING TO GCMIN ALSO EXISTS, WHICH RETURNS A
LIST SHOWING THE DEFAULT RATES FOR, IN ORDER, THE FREE STORAGE AREA,
THE FIXNUM AREA, AND THE FLONUM AREA. IN ADDITION TO THE INTERRUPTION
CAUSED BY FAILURE TO COLLECT ENOUGH SPACE, THE USERS INTERRUPT 
SERVICE FUNCTION (AS WELL AS A *RSET ERROR CATCHING FUNCTION) CAN 
COUNT ON HAVING AT LEAST  THE MINIMAL AMOUNT OF FREE SPACE IN EACH 
STORE [BUT THIS DOES NOT APPLY RECURSIVELY TO UNDERFLOWS CAUSED BY 
THE SERVICE  FUNCTION.]  IN THE CASE OF THE SERVICE FUNCTION FOR 
INTERRUPT NUMBER TEN,  IT WILL BE GIVEN AS ARGUMENT THE ATOM LIST, 
FIXNUM, OR FLONUM ACCORDING TO WHICH SPACE UNDERFLOWED.


8/30/71   - ECR - 
	THERE IS A NEW  NLISP (LISP VERSIONS 234 AND HIGHER) WHICH SHOULD
BECOME THE SYSTEM LISP IN ABOUT A MONTH.  ITS MAIN NEW FEATURE IS UNIFORM
REPRESENTATION OFNUMBERS - THE INUM KLUDGE IS GONE.  THE PURPOSE OF
THIS CHANGE IS TO ALLOW THE COMPILER TO CONTAIN A FAST-ARITHMETIC
FEATURE.  THERE IS A NEW COMPILER, LISCOM VERSIONS 129 AND HIGHER, WHICH CAN
OPEN-CODE ARITHMETIC EXPRESSIONS.  SEE LISCOM NOTE.
	USERS SHOULD TAKE NOTE OF THE FOLLOWING , IN PREPARATION FOR THE
DAY THAT NLISP BECOMES LISP:
	  1-IN NLISP , TWO NUMBERS MAY NOT BE EQ EVEN IF THEY ARE EQUAL.  NEVER
USE EQ FOR NUMBERS.  USE EQUAL OR =. (SEE BELOW FOR AN EXPLANATION OF =.)
	  2-NLISP HAS A MULTIPLE I/O FEATURE.  SEE NOTE BY RMS
	  3-THE ONLY COMPILER PRESENTLY AVAILABLE FOR USE WITH NLISP IS
NLISCOM. OTHER VERSIONS OF THE COMPILER, NAMELY OLISCOM ,LISCOM ,
AND COMPLR WILL NOT PRODUCE CODE WHICH WILL RUN IN NLISP.
IT IS EXPECTED THAT NLISP-COMPATIBLE VERSION OF COMPLR WILL BE
AVAILABLE SHORTLY, BUT SINCE IT WON'T HAVE THE FAST-ARITHMETIC FEATURE,
IT WILL STILL BE A LOSER.
	  4-THERE ARE SOME NEW ARITHMETIC OPERATIORS IN NLISP. +,-,*,/,1+,1-,\, 
ARE LIKE PLUS,DIFFERENCE, TIMES, QUOTIENT, ADD1,SUB1,REMAINDER, EXCEPT THAT THEY
TAKE ONLY FIXNUM OPERANDS.  SIMILARLY, +$,-$,*$,/$,1+$,1-$,
TAKE ONLY FLONUM OPERANDS. (INCIDENTALLY, THESE ARE REAL DOLLAR SIGNS).
THOUGH THESE WILL RUN A BIT FASTER THAN THEIR MORE FAMILIAR COUNTERPARTS,
THEIR MAIN ADVANTAGE IS THAT THEY WILL ALWAYS BE OPEN-CODED BY THE
COMPILER.  THERE ARE ALSO THREE NEW SUBR'S, =,<,>.  THEY ARE LIKE 
EQUAL, LESSP, AND GREATERP, EXCEPT THAT THEIR OPERANDS MUST BE NUMBERS
OF THE SAME TYPE (BOTH FIXNUMS OR BOTH FLONUMS).  AGAIN, THESE FUNCTIONS WILL
ALWAYS BE OPEN-COMPILED.  HOWEVER, = IS A WINNER EVEN WHEN RUNNING
INTERPREIVELY, SINCE IT CAN BE EXPECTED TO RUN MUCH FASTER THAN EQUAL.
	  5-(ZEROP 0.0) NOW RETURNS T.
	  6-A POINTER ARITHMETIC SCHEME WILL SOON BE AVAILABLE IN NLISP
FOR THOSE LOSERS WHO FOOLISHLY INSIST ON CONSING TOGETHER LOTS OF
NUMBERS.
	7- WITH NLISP, ALWAYS USE COM:NEW LAP  OR COM:NEW CLAP FOR
	   THE PROPER VERSIONS OF E LAP AND C LAP.