Here is our release of the software of Back V5.2.
Please read the following carefully; things have changed since V4.4
(compared to V5.0, the installation procedure has not changed, though).

IMPORTANT:	
    Before downloading and/or using the Back system, read the
    license agreement in file 'License.Back5'.

We recommend to read also:
 -  Syntax.Back5: 	syntax of Back V5 (compared to V4)
 -  WhatIsNew.Back52:	changes of V5.2 wrt. previous versions
 
You should have received the following files:

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Readme.Back52		% This Info
BACK-V5.intro		% Info on the BACK Project
License.Back5		% License Agreement for Downloading/Using Back
InstallQUI.Back52	% Installation File (Quintus Version)
InstallSWI.Back52	% Installation File (SWI Version)
WhatIsNew.Back52	% Documentation of changes wrt. V5.2
Syntax.Back5            % Documentation of syntax of Back V5
			% (compared to V4)
BACK-V5.ps		% Tutorial and Manual for Back V5
 
------------ TBox/ ABox Files ---------------------------

backops.pl		% operator definitions
dynamic.quintus		% dynamic predicate decls for Quintus-Prolog
quintus.library         % load file for used Quintus libary files
 
tbox1.pl 		% TBox and IBox
tbox2.pl

btl.pl 			% Term language interface
 
abox.pl 		% ABox

util.pl			% Utility file

------------ Quintus Libraries --------------------------

Subdirectory libraries	% contains Quintus libraries for usage
			% of BACK under SWI Prolog
			% Note the copyright notice in each file

basics.pl
ordsets.pl
lists.pl
sets.pl
bitsets.pl
between.pl
flatten.pl
addportray.pl
printlength.pl
types.pl


------------ Patch Files --------------------------------

back.patch

------------ Tests & Examples ---------------------------

Subdirectory tests

alltests.pl		      
cmk.abox		      
ibox_tests.pl	
jantest.abox		
jantest.iabox		
jantest.retrieval	
jantest.tbox
macro_tests.pl
revision_tests.pl
role_tests.pl
value_tests.pl
feature_tests.pl
b5tests.pl
retrievaltests.pl
displaytests.pl

------------- Back 4 to Back 5 Syntax Converter ---------

Subdirectory translate 

cf. file translate/README 

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At the moment, Back 5.2 requires Quintus Prolog or SWI-Prolog to run.

To install Back V5.2 with QUINTUS Prolog:

 -  consult 'InstallQUI.Back52'.
 

To install BACK V5.2 with SWI-Prolog:

 -  invoke SWI prolog with the following command line options:
	'prolog  -L8000 -G8000 -T8000 -A8000'

 -  consult 'InstallSWI.Back52'.
 

In both cases, to compile BACK call ':- back.'


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To get more information on how BACK works:

 -  see Syntax Reference Card;

 -  see the Manual and Tutorial for Back V5 (file 'Back5-Tutorial.ps');

 -  have a look into the test files sent with the system 
    (subdirectory tests/);

 -  see descriptions of the previous Back 4.4 version, especially 

    -  KIT Report 78 "Implementation of the BACK System Version 4"

    -  KIT Report 75 "The BACK System Revisited"


To see more examples running/ to see some abstract tests:
 
 - If you just want to know whether (almost) everything is o.k.,
   type 'backtest'; note that some tests will cause  ERROR or WARNING 
   messages which is o.k. if afterwards the message 'xxx test succeeded' 
   appears; all tests should succeed (despite it's indicated differently)

 - If you are interested in single inferences, defined roles, revision
   capabilities or retrieval functions take a look at the according test 
   files and run them by calling the topmost Prolog goal; the files 
   and their contents are as follows:
     
     cmk.abox    	: A sample TBox plus 30 ABox functionality checks
			  including tests on abox revision and application of
			  implication links 
     ibox_tests.pl	: 15 tests of IBox Inferences
     jantest.abox	: 14 tests of ABox Inferences  	
     jantest.iabox      :  9 tests of application of implications to objects
     jantest.retrieval	: two predicates testing retrieval and describe
     jantest.tbox       : 28 tests of TBox Inferences
     macro_tests.pl     :  4 tests using macros
     revision_tests.pl  :  8 tests of pure TBox revision plus 
                           4 tests of ABox adjusting after TBox revision
     role_tests.pl	: a bunch of tests on defined roles
     value_tests.pl	: a bunch of tests on attributes, numbers, and strings
     feature_tests.pl   : testing the treatment of features
     retrievaltests.pl  : 53 tests of the retrieval component
     displaytests.pl    : 53 tests of displaying results



Best regards,
 
September 9, 1993

the BACKs.
 
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