This is the release of Screamer version 3.20. Screamer 3.20 should run under Genera 8.1.1 and 8.3 on Symbolics 36xx and Ivory machines, under Lucid 4.0.2 and 4.1 on Sun SPARC machines, under Lucid 4.1 on SGI MIPS machines, under Lucid 4.1 on HP PA machines, under Lucid 4.1 on DEC MIPS machines, under Lucid 4.0.1 on IBM RS/6000 machines, under MCL 2.0 and 2.0p2 on Apple Macintosh machines, under Harlequin 3.0.3+ on Sun SPARC machines, under Allegro 4.1 and 4.2 on Sun SPARC and SGI MIPS machines, under Allegro 4.1 on DEC MIPS machines, under Poplog 14.2 on Sun SPARC machines, and under AKCL 1.605 and 1.615 on Sun SPARC machines. Note that for Lucid 4.0.2/SPARC you might want to load the patch mbmfe.sbin and for Lucid 4.1/SPARC you might want to load the patch bug-6920 (bug-6920-non-dbcs.sbin or bug-6920-dbcs.sbin as appropriate). Also note that with Lucid 4.1/HP you must load the patch file bug-5511.hbin. Also note that with Lucid 4.1/DEC you must load the patch file bug-5511.mbin. Also note that MCL requires patch level 2. If you only have MCL 2.0 without any patches or only patch level 1 you must first load the patch not-so-trivial-patch.fasl. See the notes below for more information. You are free to use, copy and distribute this software provided that: 1. You report *ALL* bugs to Bug-Screamer@AI.MIT.EDU whether or not you need them fixed. Include the version number (3.20) in the message. 2. You report *ALL* bugs that you fixed to Bug-Screamer@AI.MIT.EDU. Include the version number (3.20) in the message. 3. Every time you run Screamer on a machine or using a Lisp compiler not mentioned below, you send a message stating the new environment and the version number (3.20) to Bug-Screamer@AI.MIT.EDU. 4. You inform us that you obtained a copy of Screamer by sending a message to Info-Screamer-Request@AI.MIT.EDU to be put on the Info-Screamer@AI.MIT.EDU mailing list. Note that it may take a long time to compile Screamer (i.e. 1.5 hours using the Lucid production compiler on a Sun SPARCstation 2). This directory contains the following files: screamer.lisp - The source code for Screamer. iterate.lisp - The source code for Jonathan Amsterdam's Iterate macro. This has been modified slightly. This file is not need to run Screamer but is needed to run the examples in primordial.lisp, screams.lisp, and equations.lisp. primordial.lisp - A sort of torture test to determine whether Screamer is working. To run, first compile and load Screamer and Iterate, compile and load this file, type (IN-PACKAGE :PRIMORDIAL), and then type (PRIME-ORDEAL). If no errors result then Screamer is probably working correctly. screams.lisp - A file containing all of the examples from the Screamer manual and the two papers ircs-93-03 and aaai93. To use, first compile and load Screamer and Iterate, compile and load this file, and then type (IN-PACKAGE :SCREAMS). equations.lisp - A file containing some equations for testing Screamer's numeric constraint satisfaction procedures. To use, first compile and load Screamer, compile and load this file, and then type (IN-PACKAGE :SCREAMS). mbmfe.sbin - A patch for Lucid 4.0.2/SPARC. This patch is optional but will make the compiled code tail recursive in an greater number of cases. You should either load this in your lisp-init.lisp file or make it part of your standard image. This patch is already part of Lucid 4.1/SPARC so should not be loaded if you are running 4.1 on SPARC machines. bug-6920-non-dbcs.sbin - Lucid 4.0.2/SPARC and 4.1/SPARC are both missing the CLtL2 function REALP which is needed by Screamer. This patch from Lucid adds that function but will only work under non-DBCS 4.1/SPARC. The file screamer.lisp also contains a definition of REALP so you have three choices: a) If you run 4.0.2/SPARC do NOT load this patch. The version in screamer.lisp will be used automatically. b) If you run 4.1/SPARC you can choose not to load this patch and the version in screamer.lisp will be used automatically. c) If you run 4.1/SPARC and doload this patch then you MUST also evaluate (PUSH :BUG-6920 *FEATURES* ) before compiling Screamer to disable the inclusion of the Screamer version of the REALP function. bug-6920-dbcs.sbin - A DBCS version of the patch for bug-6920 for Lucid 4.1/SPARC. bug-5511.hbin - Lucid 4.1/HP has a bug. This patch must be loaded to fix that bug when compiling or using Screamer under Lucid 4.1/HP. bug-5511.mbin - Lucid 4.1/DEC has a bug. This patch must be loaded to fix that bug when compiling or using Screamer under Lucid 4.1/DEC. not-so-trivial-patch.fasl.hqx - A patch for MCL 2.0 in BinHex 4.0 format. If you are running a version prior to patch level 2 this patch is required to fix a code generator bug in the MCL compiler necessary to correctly compile Screamer. If you are running patch level 2 or greater you should not load this patch as it is already included in patch level 2. iscream.el - If you run Lisp on Unix under GNUEmacs using ILisp you can load this Emacs Lisp file (preferably byte compiled first). You must also then set the variable SCREAMER:*ISCREAM?* to T. This will enable the Screamer macro LOCAL-OUTPUT and improve the behavior of Y-OR-N-P and PRINT-VALUES under ILisp. screamer.dvi screamer.ps - DVI and Postscript versions of an outdated manual for Screamer. The code in this manual has some bugs but corrected versions are included in screams.lisp. ircs-93-03.dvi ircs-93-03.ps - DVI and Postscript versions of a paper describing the fundamentals of nondeterministic CommonLisp. This paper is available at Technical Report 93-03 of the University of Pennsylvania Institute for Research in Cognitive Science. The appropriate BibTeX entry is: \newcommand{\Screamer}{{\mbox{\sc Screamer}}} \newcommand{\CommonLisp}{{\mbox{\sc Common Lisp}}} @string{IRCS = {University of Pennsylvania Institute for Research in Cognitive Science}} @techreport{SiskindM93, author = {Jeffrey Mark Siskind and David Allen McAllester}, title = {{\Screamer:} A Portable Efficient Implementation of Nondeterministic {\CommonLisp}}, institution = IRCS, year = 1993, number = {IRCS--93--03}} The code in this paper is included in screams.lisp. aaai93.dvi aaai93.ps - DVI and Postscript versions of a paper describing the constraint package included with Screamer. This paper will appear in the Proceedings of AAAI-93. The appropriate BibTeX entry is: The code in this paper is also included in screams.lisp. \newcommand{\Lisp}{{\mbox{\sc Lisp}}} @string{AAAI93 = {Proceedings of the Eleventh National Conference on Artifical Intelligence}} @inproceedings{SiskindM93a, author = {Jeffrey Mark Siskind and David Allen McAllester}, title = {Nondeterministic {\Lisp} as a Substrate for Constraint Logic Programming}, booktitle = AAAI93, year = 1993, month = jul} Incompatibilities between Screamer 3.20 and Screamer 2.4: Screamer 3.20 contains numerous bug fixes, performance enhancements and novel features over Screamer 2.4, the prior widely released version. I do not have the time to describe all such improvements. Until the completion of a new Screamer manual you must resort to looking at the source code. At the beginning of the file there is a fairly extensive change log. A small number of incompatibilities have been introduced in the transition from Screamer 2.4 to Screamer 3.20. These are summarized below. Those already familiar with Screamer should have no difficulty modifying their code modulo these changes. 1. All Screamer code must be recompiled. The Screamer 3.20 runtime is incompatibile with the Screamer 2.4 compiler. 2. The function MAP-VALUES has been removed. An expression such as: (MAP-VALUES function expression) can be rewritten using the new FOR-EFFECTS macro as follows: (FOR-EFFECTS (FUNCALL function expression)) The new syntax is every bit as powerful as the old syntax. In fact it is more powerfull. MAP-VALUES used to require that the function argument be a deterministic expression while the new syntax makes no such requirement. (Note that FUNCALL still requires that its first argument evaluate to a deterministic function.) 3. You no longer need to reload Screamer after doing an UNWEDGE-SCREAMER since Screamer keeps track of which functions are intrinsic and UNWEDGE-SCREAMER does not purge those functions. 4. The following functions have been renamed: NUMBERV -> NUMBERPV REALV -> REALPV INTEGERV -> INTEGERPV BOOLEANV -> BOOLEANPV The original names were inconsistent with the naming convention that every function ending in V names a lifted version of the function name without the V. I.e. NUMBERV would have been a lifted version of a function NUMBER but there is no ground function. NUMBERV was really a lifted version of NUMBERP and thus should have been named NUMBERPV. 5. A new naming convention has been introduced. All nondeterministic `generators' now begin with the prefix A- or AN-. This results in the following name changes: INTEGER-BETWEEN -> AN-INTEGER-BETWEEN MEMBER-OF -> A-MEMBER-OF FLIP -> A-BOOLEAN Furthermore, `lifted generators' both begin with A- or AN- and end with V. This results in the following name changes: REAL-ABOVEV -> A-REAL-ABOVEV REAL-BELOWV -> A-REAL-BELOWV REAL-BETWEENV -> A-REAL-BETWEENV INTEGER-ABOVEV -> AN-INTEGER-ABOVEV INTEGER-BELOWV -> AN-INTEGER-BELOWV INTEGER-BETWEENV -> AN-INTEGER-BETWEENV 6. The variable *FUZZ* has been eliminated. The functionality of this variable has been replaced by additional arguments to the REORDER function. 7. REORDER now takes four arguments: (COST-FUNCTION TERMINATE? ORDER FORCE-FUNCTION) instead of one. The FORCE-FUNCTION is the same as the prior lone argument. The COST-FUNCTION is a function to be applied to each VARIABLE at each reordering step to return its cost. Typical values for COST-FUNCTION are #'DOMAIN-SIZE or #'RANGE-SIZE. The COST-FUNCTION can return NIL which causes REORDER to not consider that variable for further forcing. ORDER is a two argument predicate applied to the non-NIL cost functions computed for the variables at each reordering step. Typical values are #'<, to choose the least cost, and #'>, to choose the greatest cost variable to force next. TERMINATE? is a one argument predicate applied to the (non-NIL) cost function computed for the variable chosen to force next. If TERMINATE? returns T then the variable reordering and forcing terminates. The following is a typical call to REORDER used to solve numerical constraints: (REORDER #'RANGE-SIZE #'(LAMBDA (X) (< X 1E-6)) #'> #'DIVIDE-AND-CONQUER-FORCE) The following is a typical call to REORDER used to solve symbolic constraints: (REORDER #'DOMAIN-SIZE #'(LAMBDA (X) (DECLARE (IGNORE X)) NIL) #'< #'LINEAR-FORCE) 8. Instead of the standard Screamer file preamble which used to be: (IN-PACKAGE :) (USE-PACKAGE '(:LISP :SCREAMER)) (SHADOWING-IMPORT '(SCREAMER::DEFUN)) there is now a different standard preamble. Loading Screamer creates a predefined package SCREAMER-USER which is useful for small student and demonstration programs. If you wish your file to be in the SCREAMER-USER package the single line: (IN-PACKAGE :SCREAMER-USER) should be placed at the top of the file. In addition: (IN-PACKAGE :SCREAMER-USER) should be typed to the Listener after loading Screamer. More complex programs typically reside in their own package. You can place a program in its own package by using the following preamble to your file: (IN-PACKAGE :CL-USER) (SCREAMER:DEFINE-SCREAMER-PACKAGE : ) (IN-PACKAGE :MY-PACKAGE) Note that DEFINE-SCREAMER-PACKAGE doesn't work under AKCL or Poplog so on these systems you must either use the SCREAMER-USER package or figure out on your own how to appropriately define a Screamer package.