Logtalk 2.29.1 files.

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1744 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

Logtalk/BIBLIOGRAPHY.bib

@@ -2,7 +2,7 @@
 @misc{logtalkweb,
 	author = "Paulo Moura",
 	title = "Logtalk web site",
-	howpublished = "\url{http://www.logtalk.org/}"
+	howpublished = "\url{http://logtalk.org/}"
 }
 
 
@@ -33,7 +33,7 @@
 	school = "Department of Informatics, University of Beira Interior, Portugal",
 	month = sep,
 	year = 2003,
-	howpublished = "\url{http://www.logtalk.org/papers/thesis.pdf}"
+	howpublished = "\url{http://logtalk.org/papers/thesis.pdf}"
 }
 
 
@@ -42,7 +42,7 @@
 	Title = "{Category-Based Composition in Object-Oriented Languages}",
 	month = nov,
 	year = 2000,
-	howpublished = "\url{http://www.logtalk.org/papers/categories_ecoop.pdf}",
+	howpublished = "\url{http://logtalk.org/papers/categories_ecoop.pdf}",
 	annote = "Submitted to ECOOP 2001"
 }
 
@@ -54,7 +54,7 @@
 	number = "DMI 2000/1",
 	month = jul,
 	year = 2000,
-	howpublished = "\url{http://www.logtalk.org/files/trdmi20001a4.pdf.gz}"
+	howpublished = "\url{http://logtalk.org/files/trdmi20001a4.pdf.gz}"
 }
 
 
@@ -63,7 +63,7 @@
 	Title = "{Category-Based Composition in Object-Oriented Languages}",
 	month = apr,
 	year = 2000,
-	howpublished = "\url{http://www.logtalk.org/papers/categories_oopsla.pdf}",
+	howpublished = "\url{http://logtalk.org/papers/categories_oopsla.pdf}",
 	annote = "Submitted to OOPSLA 2000"
 }
 

Logtalk/CUSTOMIZE.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -9,7 +9,8 @@ Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 This file contains detailed instructions for customizing your Logtalk 
 installation and working environment. Customization is mostly done on 
 a per-user basis by editing files on the Logtalk user folder (whose 
-path is sorted on the LOGTALKUSER environment variable).
+path is stored on the LOGTALKUSER environment variable; the folder itself 
+can be created by running the "cplgtdirs" shell command).
 
 
 1. SETTING LIBRARY PATHS

Logtalk/INSTALL.txt

@@ -1,16 +1,17 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
 
 
-This file contains detailed instructions for installing and configuring 
+The recommended way of installing Logtalk is to use, whenever possible, one 
-Logtalk. You should also consult the "scripts/NOTES" file for a description 
+of the provided installers. This file contains detailed instructions for 
-of a set of shell scripts that might be used for Logtalk installation on 
+manual installation and configuration of Logtalk. You should also consult 
-some operating-systems and for easy Logtalk integration with popular 
+the "scripts/NOTES" file for a description of a set of shell scripts that 
-Prolog compilers.
+might be used for Logtalk installation on some operating-systems and for 
+easy Logtalk integration with popular Prolog compilers.
 
 Note that the broad compatibility of Logtalk, both with Prolog compilers and 
 operating-systems, together with all the possible user scenarios, means that 

Logtalk/QUICK_START.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -10,32 +10,36 @@ Quick start
 ===========
 
 
-1. Install Logtalk by following the instructions on the "INSTALL" file. 
+1. Install Logtalk by using either the installer provided for your 
-Depending on your operating-system, working environment, and favorite 
+operating-system (when available) or by following the instructions 
-Prolog compiler, you may already have a script or a shortcut installed 
+on the "INSTALL" file. Depending on your operating-system, working 
-for easily running Logtalk with your favorite Prolog compiler. If so, 
+environment, and favorite Prolog compiler, you may already have a 
-skip the instructions below for starting up Logtalk.
+script or a shortcut installed for easily running Logtalk with your 
+favorite Prolog compiler. If so, skip the instructions below for 
+starting up Logtalk.
 
 2. Open the "manuals/index.html" file with a web browser.
 
-3. Select the "Tutorial" link. This will provide you with a basic understanding
+3. Select the "Tutorial" link. This will provide you with a basic 
-of the main Logtalk concepts.
+understanding of the main Logtalk concepts.
 
-4. Go back to the "index.html" file and select the "User Manual" link and then 
+4. Go back to the "index.html" file and select the "User Manual" 
-the Installing and running Logtalk links. This will provide you with a basic 
+link and then the Installing and running Logtalk links. This will 
-understanding of how to start Logtalk and compile and load Logtalk code.
+provide you with a basic understanding of how to start Logtalk and 
+compile and load Logtalk code.
 
 
 Assuming that Logtalk supports your Prolog compiler:
 
-1. Read the "NOTES" file in the "configs" sub-directory to check if any patch 
+1. Read the "NOTES" file in the "configs" sub-directory to check if 
-or workaround is needed for your compiler.
+any patch or workaround is needed for your compiler.
 
 2. Start your Prolog compiler.
 
-3. Change the current working directory of your Prolog session to the Logtalk 
+3. Change the current working directory of your Prolog session to the 
-installation directory. If you don't know which predicate to use, check the 
+Logtalk installation directory. If you don't know which predicate to 
-"configs/NOTES" file or your Prolog compiler reference manual.
+use, check the "configs/NOTES" file or your Prolog compiler reference 
+manual.
 
 4. Compile and load the config file for your Prolog compiler.
 
@@ -75,18 +79,18 @@ them on your Prolog interpreter top-level.
 
 Ready to start writing your own programs?
 
-1. Read the User Manual sections on "Programming in Logtalk" and "Running and 
+1. Read the User Manual sections on "Programming in Logtalk" and "Running 
-debugging Logtalk programs".
+and debugging Logtalk programs".
 
 2. Take a look at the "wenv" sub-directory. There you will find syntax 
 configuration files for popular text editors that enable syntax coloring 
 and other goodies when editing Logtalk source files.
 
-3. Create a sub-directory with a suitable name to hold all the files of your 
+3. Create a sub-directory with a suitable name to hold all the files of 
-application. You may want to add the directory path to the libpaths.pl file 
+your application. You may want to add the directory path to the libpaths.pl 
-mentioned above in order to easily load your application.
+file mentioned above in order to easily load your application.
 
-4. Copy to this sub-directory a loader file from one of the example directories
+4. Copy to this sub-directory a loader file from one of the example 
-and modify it to load your own source files.
+directories and modify it to load your own source files.
 
 5. Have fun!

Logtalk/README.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -81,7 +81,8 @@ with just the word "help" in the subject or in the message body.
 
 Logtalk can be installed either from sources by running a few shell scripts 
 or by using one of the provided installers, depending on your operating 
-system. See the file "INSTALL.txt" for detailed instructions.
+system. For manual installation, see the file "INSTALL.txt" for detailed 
+instructions.
 
 See the user manual for a description of the source files organization 
 and for using instructions (to read the user manual open the file 

Logtalk/RELEASE_NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -10,6 +10,102 @@ RELEASE NOTES
 =============
 
 
+2.29.1 - December 28, 2006
+
+	Added a Logtalk version of John Fletcher's Prolog XML parser (see the 
+	folder "contributions/xml_parser").
+
+	Added shell scripts for helping building the distribution files of a 
+	new Logtalk release. Updated the MacOS X installer package to set 
+	default values for the Logtalk environment variables. Corrected a bug 
+	in the logtalk.spec file where the default value for the LOGTALKUSER 
+	environment variable only worked for the user doing the RPM installation.
+
+	Corrected a bug in the reporting of the line number where a compilation 
+	error (or warning) occurred. Extended support for reporting warning and 
+	error line numbers to Quintus Prolog, Ciao Prolog, Qu-Prolog, and 
+	ECLiPSe.
+
+	Corrected a bug when using partial lists with the predicates nth0/3-4 
+	and nth1/3-4 provided by the "list" library object.
+
+	Improved "philosophers" multi-threading programming example.
+
+
+2.29.0 - December 18, 2006
+
+	Added a new built-in, empty object named "logtalk", which can play the 
+	role of both a class and a prototype. It may be used to define class 
+	hierarchies without forcing the use of metaclasses or reflective 
+	designs.
+
+	Added a built-in protocol named "monitoring" with declarations for 
+	the before/3 and after/3 public event handler predicates. Updated 
+	the Logtalk compiler to print a warning when defining an event handler 
+	with no reference to the "monitoring" protocol.
+
+	The default value of the compiler flag events/1 is now off. As most 
+	applications do not use events, this setting ensures the best possible 
+	message processing performance for those applications.
+
+	Removed the experimental threaded_call/2 and threaded_exit/2 thread 
+	predicates, replaced by new threaded_once/1, threaded_ignore/1, 
+	threaded_race/1, threaded_peek/1, and threaded_discard/1 predicates.
+	Renamed predicate directive atomic/1 to synchronized/1. Added new 
+	entity directive synchronized/0. Added support for new "synchronized" 
+	and "threaded" entity properties.
+
+	Corrected a bug when using threaded calls as initialization goals 
+	within threaded objects.
+
+	Corrected an elusive bug in the Logtalk compiler where a source file 
+	may not be properly closed when it contains a syntax error (thanks 
+	to Robert Shiplett for the bug report).
+
+	Corrected a bug in the implementation of the built-in methods retract/1 
+	and retractall/1 that could result in unexpected exceptions. Updated 
+	the built-in method assertz/1 to always use the lookup cache.
+
+	Corrected a bug in the compilation of empty classes that are not 
+	instances of a metaclass.
+
+	Corrected a bug in the built-in method predicate_property/2 where some 
+	predicate properties may not be returned when enumerating properties 
+	using backtracking.
+
+	Modified the SWI-Prolog config file and integration scripts to set 
+	the flag "iso" to "true". Corrected an elusive bug in the definition 
+	of predicate '$lgt_directory_exists'/1 that resulted in "library not 
+	found" errors when loading Logtalk source files from within the 
+	SWI-Prolog initialization file (thanks to Robert Shiplett for the bug 
+	report).
+
+	Updated the K-Prolog config file to workaround a problem when using 
+	library notation due to failure to check directory existence with the 
+	provided "libpaths.pl" file.
+
+	Added a RELAX NG file describing the structure of the XML documenting 
+	files generated by Logtalk.
+
+	Corrected a bug in the Logtalk DTD file (missing "copyright" tag 
+	declaration).
+
+	Corrected a bug in the lgt2*.js scripts where the "custom.ent" file 
+	was not being copied when generating (X)HTML and PDF files.
+
+	Added a new multi-threading example, "philosophers", illustrating a 
+	possible implementation of the "dining philosophers" problem.
+
+	Improved the "metapredicates" example in order to illustrate the use 
+	of closures instead of goals as meta-arguments.
+
+	Added a reference to the "e" Windows text editor, which supports 
+	the MacOS X TextMate 1.x text editor syntax configuration files.
+	
+	Updated the manuals index pages in order to workaround browsers bugs 
+	with parsing of empty "span" tags (e.g. Internet Explorer and Opera).
+
+
 2.28.2 - November 6, 2006
 
 	Corrected a compiler bug where unknown entities will not be report when 

Logtalk/UPGRADING.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -140,5 +140,15 @@ could be used to bypass predicate scope declarations, meta-predicates that
 use closures must be re-implemented to use the new call/N Logtalk built-in 
 predicate. The directive metapredicate/1 is now deprecated, the directive 
 meta_predicate/1 should be used instead. There are also changes to the 
-config files that render the Logtalk runtime imcompatible with the config 
+config files that render the Logtalk runtime incompatible with the config 
 files of previous versions.
+
+Logtalk 2.29.0 makes some incompatible changes to the experimental support 
+for multi-threading programming that may imply updating any application that 
+uses the multi-threading predicates. The default value of the compiler flag 
+events/1 is now off. Applications using event-driven programming must either 
+turn this flag on or compile source files with the events(on) option. The 
+library protocol "event_handlersp" is now deprecated; new code should use 
+instead the built-in "monitoring" protocol. The new support for "threaded" 
+and "synchronized" entity properties implies implying recompilation of all 
+objects and categories.

Logtalk/contributions/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -18,3 +18,9 @@ iso8601.lgt
 	one of the documentation helper scripts to transform the 
 	resulting XML file into (X)HTML or PDF documentation. Your 
 	feedback is appreciated.
+
+xml_parser
+	Contributed by: John Fletcher
+
+	This folder contains a Logtalk version of John Fletcher's 
+	Prolog XML parser (http://www.zen37763.zen.co.uk/xml.pl.html).

Logtalk/contributions/xml_parser/NOTES.txt

@@ -0,0 +1,19 @@
+=================================================================
+Logtalk - Object oriented extension to Prolog
+Release 2.29.1
+
+Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
+=================================================================
+
+
+This folder contains a Logtalk version of John Fletcher's Prolog XML 
+parser:
+
+	http://www.zen37763.zen.co.uk/xml.pl.html
+
+To load this XML parser and for sample queries, please see the SCRIPT 
+file.
+
+For a detailed description of this XML parser, please see the comments 
+in the "xml.lgt" source file or convert the automatically generated 
+documentation to HTML or PDF.

Logtalk/contributions/xml_parser/SCRIPT.txt

@@ -0,0 +1,34 @@
+=================================================================
+Logtalk - Object oriented extension to Prolog
+Release 2.29.1
+
+Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
+=================================================================
+
+
+% start by loading the necessary library support files (if not 
+% already loaded):
+
+| ?- logtalk_load(library(types_loader)).
+...
+
+
+% now you are ready for loading the XML parser:
+
+| ?- logtalk_load(xml_parser(loader)).
+...
+
+
+% let's try some examples (the goals generate XML files named qi.xml):
+
+| ?- logtalk_load(xml_parser(examples)).
+...
+
+|  ?- test(q1).
+...
+
+|  ?- test(q2).
+...
+
+|  ?- test(q12).
+...

Logtalk/contributions/xml_parser/bib.xml

@@ -0,0 +1,36 @@
+<bib>
+    <book year="1994">
+        <title>TCP/IP Illustrated</title>
+        <author><last>Stevens</last><first>W.</first></author>
+        <publisher>Addison-Wesley</publisher>
+        <price> 65.95</price>
+    </book>
+ 
+    <book year="1992">
+        <title>Advanced Programming in the Unix environment</title>
+        <author><last>Stevens</last><first>W.</first></author>
+        <publisher>Addison-Wesley</publisher>
+        <price>65.95</price>
+    </book>
+ 
+    <book year="2000">
+        <title>Data on the Web</title>
+        <author><last>Abiteboul</last><first>Serge</first></author>
+        <author><last>Buneman</last><first>Peter</first></author>
+        <author><last>Suciu</last><first>Dan</first></author>
+        <publisher>Morgan Kaufmann Publishers</publisher>
+        <price>39.95</price>
+    </book>
+ 
+    <book year="1999">
+        <title>The Economics of Technology and Content for Digital TV</title>
+        <editor>
+               <last>Gerbarg</last><first>Darcy</first>
+                <affiliation>CITI</affiliation>
+        </editor>
+            <publisher>Kluwer Academic Publishers</publisher>
+        <price>129.95</price>
+    </book>
+ 
+</bib>
+

Logtalk/contributions/xml_parser/books.xml

@@ -0,0 +1,15 @@
+<chapter>
+    <title>Data Model</title>
+    <section>
+        <title>Syntax For Data Model</title>
+    </section>
+    <section>
+        <title>XML</title>
+        <section>
+            <title>Basic Syntax</title>
+        </section>
+        <section>
+            <title>XML and Semistructured Data</title>
+        </section>
+    </section>
+</chapter>

Logtalk/contributions/xml_parser/examples.lgt

@@ -0,0 +1,387 @@
+/* Using xml.pl to solve XML Query Cases - An Example
+ *
+ * The following is a complete example to illustrate how the module can be used;
+ * it exercises both the input and output parsing modes of xml::parse/[2,3], and
+ * illustrates the use of xml::subterm/2 to access the nodes of a "document value
+ * model". It's written for Quintus Prolog, but should port to other Prologs
+ * easily.
+ *
+ * The entry-point of the program is the test/1 predicate.
+ *
+ * test( +QueryId ) executes a Prolog implementation of a Query from Use Case
+ * "XMP": Experiences and Exemplars, in the W3C's XML Query Use Cases, which
+ * "contains several example queries that illustrate requirements gathered from
+ * the database and document communities".
+ * <http://www.w3.org/TR/2002/WD-xmlquery-use-cases-20021115/#xmp>
+ *
+ * QueryId is one of q1…q12 selecting which of the 12 use cases is executed.
+ * The XML output is written to the file [QueryId].xml in the current directory.
+ *
+ * xml::pp/1 is used to display the resulting "document value model"
+ % data-structures on the user output (stdout) stream.
+ */
+test( Query ) :-
+	xml_query( Query, ResultElement ),
+	% Parse output XML into the Output chars
+	xml::parse( Codes, xml([], [ResultElement]) ),
+	atom_concat( Query, '.xml', OutputFile ),
+	% Write OutputFile from the Output list of chars
+	open( OutputFile, write, Output ),
+	put_codes( Codes, Output ),
+	close( Output ),
+	% Pretty print OutputXML
+	write( 'Output XML' ), nl,
+	xml::pp( xml([], [ResultElement]) ).
+
+/* xml_query( +QueryNo, ?OutputXML ) when OutputXML is an XML Document Value Model
+ * produced by running an example taken, identified by QueryNo from the XML Query
+ * "XMP" use case.
+ */
+
+% Q1: List books published by Addison-Wesley after 1991, including their year and
+% title.
+
+xml_query( q1, element(bib, [], Books) ) :-
+	element_name( Title, title ),
+	element_name( Publisher, publisher ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		element(book, [year=Year], [Title]),
+		(
+		xml::subterm( Bibliography, element(book, Attributes, Content) ),
+		xml::subterm( Content, Publisher ),
+		xml::subterm( Publisher, Text ),
+		text_value( Text, "Addison-Wesley" ),
+		list::member( year=Year, Attributes ),
+		number_codes( YearNo, Year ),
+		YearNo > 1991,
+		xml::subterm( Content, Title )
+		),
+		Books
+	).
+
+% Q2: Create a flat list of all the title-author pairs, with each pair enclosed
+% in a "result" element.
+
+xml_query( q2, element(results, [], Results) ) :-
+	element_name( Title, title ),
+	element_name( Author, author ),
+	element_name( Book, book ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		element(result, [], [Title,Author]),
+		(
+		xml::subterm( Bibliography, Book ),
+		xml::subterm( Book, Title ),
+		xml::subterm( Book, Author )
+		),
+		Results
+	).
+
+% Q3: For each book in the bibliography, list the title and authors, grouped
+% inside a "result" element.
+
+xml_query( q3, element(results, [], Results) ) :-
+	element_name( Title, title ),
+	element_name( Author, author ),
+	element_name( Book, book ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		element(result, [], [Title|Authors]),
+		(
+		xml::subterm( Bibliography, Book ),
+		xml::subterm( Book, Title ),
+		findall( Author, xml::subterm(Book, Author), Authors )
+		),
+		Results
+	).
+
+% Q4: For each author in the bibliography, list the author's name and the titles
+% of all books by that author, grouped inside a "result" element.
+
+xml_query( q4, element(results, [], Results) ) :-
+	element_name( Title, title ),
+	element_name( Author, author ),
+	element_name( Book, book ),
+	input_document( 'bib.xml', Bibliography ),
+	findall( Author, xml::subterm(Bibliography, Author), AuthorBag ),
+	sort( AuthorBag, Authors ),
+	findall(
+		element(result, [], [Author|Titles]),
+		(
+		list::member( Author, Authors ),
+		findall( Title, (
+			xml::subterm( Bibliography, Book ),
+			xml::subterm( Book, Author ),
+			xml::subterm( Book, Title )
+			),
+			Titles
+			)
+		),
+		Results
+	).
+
+% Q5: For each book found at both bn.com and amazon.com, list the title of the
+% book and its price from each source.
+
+xml_query( q5, element('books-with-prices', [], BooksWithPrices) ) :-
+	element_name( Title, title ),
+	element_name( Book, book ),
+	element_name( Review, entry ),
+	input_document( 'bib.xml', Bibliography ),
+	input_document( 'reviews.xml', Reviews ),
+	findall(
+		element('book-with-prices', [], [
+			Title,
+			element('price-bn',[], BNPrice ),
+			element('price-amazon',[], AmazonPrice )
+			] ),
+		(
+		xml::subterm( Bibliography, Book ),
+		xml::subterm( Book, Title ),
+		xml::subterm( Reviews, Review ),
+		xml::subterm( Review, Title ),
+		xml::subterm( Book, element(price,_, BNPrice) ),
+		xml::subterm( Review, element(price,_, AmazonPrice) )
+		),
+		BooksWithPrices
+	).
+
+% Q6: For each book that has at least one author, list the title and first two
+% authors, and an empty "et-al" element if the book has additional authors.
+
+xml_query( q6, element(bib, [], Results) ) :-
+	element_name( Title, title ),
+	element_name( Author, author ),
+	element_name( Book, book ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		element(book, [], [Title,FirstAuthor|Authors]),
+		(
+		xml::subterm( Bibliography, Book ),
+		xml::subterm( Book, Title ),
+		findall( Author, xml::subterm(Book, Author), [FirstAuthor|Others] ),
+		other_authors( Others, Authors )
+		),
+		Results
+	).
+
+% Q7: List the titles and years of all books published by Addison-Wesley after
+% 1991, in alphabetic order.
+
+xml_query( q7, element(bib, [], Books) ) :-
+	element_name( Title, title ),
+	element_name( Publisher, publisher ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		Title-element(book, [year=Year], [Title]),
+		(
+		xml::subterm( Bibliography, element(book, Attributes, Book) ),
+		xml::subterm( Book, Publisher ),
+		xml::subterm( Publisher, Text ),
+		text_value( Text, "Addison-Wesley" ),
+		list::member( year=Year, Attributes ),
+		number_codes( YearNo, Year ),
+		YearNo > 1991,
+		xml::subterm( Book, Title )
+		),
+		TitleBooks
+	),
+	keysort( TitleBooks, TitleBookSet ),
+	range( TitleBookSet, Books ).
+
+% Q8: Find books in which the name of some element ends with the string "or" and
+% the same element contains the string "Suciu" somewhere in its content. For each
+% such book, return the title and the qualifying element.
+
+xml_query( q8, element(bib, [], Books) ) :-
+	element_name( Title, title ),
+	element_name( Book, book ),
+	element_name( QualifyingElement, QualifyingName ),
+	list::append( "Suciu", _Back, Suffix ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		element(book, [], [Title,QualifyingElement]),
+		(
+		xml::subterm( Bibliography, Book ),
+		xml::subterm( Book, QualifyingElement ),
+		atom_codes( QualifyingName, QNChars ),
+		list::append( _QNPrefix, "or", QNChars ),
+		xml::subterm( QualifyingElement, TextItem ),
+		text_value( TextItem, TextValue ),
+		list::append( _Prefix, Suffix, TextValue ),
+		xml::subterm( Book, Title )
+		),
+		Books
+	).
+
+% Q9: In the document "books.xml", find all section or chapter titles that
+% contain the word "XML", regardless of the level of nesting.
+
+xml_query( q9, element(results, [], Titles) ) :-
+	element_name( Title, title ),
+	list::append( "XML", _Back, Suffix ),
+	input_document( 'books.xml', Books ),
+	findall(
+		Title,
+		(
+		xml::subterm( Books, Title ),
+		xml::subterm( Title, TextItem ),
+		text_value( TextItem, TextValue ),
+		list::append( _Prefix, Suffix, TextValue )
+		),
+		Titles
+	).
+
+% Q10: In the document "prices.xml", find the minimum price for each book, in the
+% form of a "minprice" element with the book title as its title attribute.
+
+xml_query( q10, element(results, [], MinPrices) ) :-
+	element_name( Title, title ),
+	element_name( Price, price ),
+	input_document( 'prices.xml', Prices ),
+	findall( Title, xml::subterm(Prices, Title), TitleBag ),
+	sort( TitleBag, TitleSet ),
+	element_name( Book, book ),
+	findall(
+		element(minprice, [title=TitleString], [MinPrice]),
+		(
+		list::member( Title, TitleSet ),
+		xml::subterm( Title, TitleText ),
+		text_value( TitleText, TitleString ),
+		findall( PriceValue-Price, (
+			xml::subterm( Prices, Book ),
+			xml::subterm( Book, Title ),
+			xml::subterm( Book, Price ),
+			xml::subterm( Price, Text ),
+			text_value( Text, PriceChars ),
+			number_codes( PriceValue, PriceChars )
+			),
+			PriceValues
+			),
+		minimum( PriceValues, PriceValue-MinPrice )
+		),
+		MinPrices
+	).
+
+% Q11: For each book with an author, return the book with its title and authors.
+% For each book with an editor, return a reference with the book title and the
+% editor's affiliation.
+
+xml_query( q11, element(bib, [], Results) ) :-
+	element_name( Title, title ),
+	element_name( Author, author ),
+	element_name( Book, book ),
+	element_name( Editor, editor ),
+	element_name( Affiliation, affiliation ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		element(book, [], [Title,FirstAuthor|Authors]),
+		(
+		xml::subterm( Bibliography, Book ),
+		xml::subterm( Book, Title ),
+		findall( Author, xml::subterm(Book, Author), [FirstAuthor|Authors] )
+		),
+		Books
+	),
+	findall(
+		element(reference, [], [Title,Affiliation]),
+		(
+		xml::subterm( Bibliography, Book ),
+		xml::subterm( Book, Title ),
+		xml::subterm( Book, Editor ),
+		xml::subterm( Editor, Affiliation )
+		),
+		References
+	),
+	list::append( Books, References, Results ).
+
+% Q12: Find pairs of books that have different titles but the same set of authors
+% (possibly in a different order).
+
+xml_query( q12, element(bib, [], Pairs) ) :-
+	element_name( Author, author ),
+	element_name( Book1, book ),
+	element_name( Book2, book ),
+	element_name( Title1, title ),
+	element_name( Title2, title ),
+	input_document( 'bib.xml', Bibliography ),
+	findall(
+		element('book-pair', [], [Title1,Title2]),
+		(
+		xml::subterm( Bibliography, Book1 ),
+		findall( Author, xml::subterm(Book1, Author), AuthorBag1 ),
+		sort( AuthorBag1, AuthorSet ),
+		xml::subterm( Bibliography, Book2 ),
+		Book2 @< Book1,
+		findall( Author, xml::subterm(Book2, Author), AuthorBag2 ),
+		sort( AuthorBag2, AuthorSet ),
+		xml::subterm( Book1, Title1 ),
+		xml::subterm( Book2, Title2 )
+		),
+		Pairs
+	).
+
+% Auxilliary Predicates
+
+other_authors( [], [] ).
+other_authors( [Author|Authors], [Author|EtAl] ) :-
+	et_al( Authors, EtAl ).
+
+et_al( [], [] ).
+et_al( [_|_], [element('et-al',[],[])] ).
+
+text_value( [pcdata(Text)], Text ).
+text_value( [cdata(Text)], Text ).
+
+element_name( element(Name, _Attributes, _Content), Name ).
+
+
+/* range( +Pairs, ?Range ) when Pairs is a list of key-datum pairs and Range
+ * is the list of data.
+ */
+range( [], [] ).
+range( [_Key-Datum|Pairs], [Datum|Data] ) :-
+	range( Pairs, Data ).
+
+/* minimum( +List, ?Min ) is true if Min is the least member of List in the
+ * standard order.
+ */
+minimum( [H|T], Min ):-
+	minimum1( T, H, Min ).
+
+minimum1( [], Min, Min ).
+minimum1( [H|T], Min0, Min ) :-
+	compare( Relation, H, Min0 ),
+	minimum2( Relation, H, Min0, T, Min ).
+
+minimum2( '=', Min0, Min0, T, Min ) :-
+	minimum1( T, Min0, Min ).
+minimum2( '<', Min0, _Min1, T, Min ) :-
+	minimum1( T, Min0, Min ).
+minimum2( '>', _Min0, Min1, T, Min ) :-
+	minimum1( T, Min1, Min ).
+
+/* input_document( +File, ?XML ) reads File and parses the input into the
+ * "Document Value Model" XML.
+ */
+input_document( File, XML ) :-
+	% Read InputFile as a list of chars
+	open( File, read, Input ),
+	get_codes( Input, Codes ),
+	close( Input ),
+	% Parse the Input chars into the term XML
+	xml::parse( Codes, XML ).
+
+
+put_codes( [], _ ).
+put_codes( [Code|Codes], Output ) :-
+	put_code( Output, Code ),
+	put_codes( Codes, Output ).
+
+	
+get_codes( Input, [Code|Codes] ) :-
+	\+ at_end_of_stream( Input ),
+	get_code( Input, Code ),
+	get_codes( Input, Codes ).
+get_codes( _, [] ).

Logtalk/contributions/xml_parser/loader.lgt

@@ -0,0 +1,13 @@
+
+:- initialization(
+	logtalk_load(xml)). 
+
+/*
+If you intend to use the FOP XSL:FO processor for generating PDF documenting
+files, comment the directive above and uncomment the directive below
+
+:- initialization(
+	logtalk_load(
+		xml,
+		[xmlsref(standalone)])).
+*/

Logtalk/contributions/xml_parser/prices.xml

@@ -0,0 +1,32 @@
+<prices>
+    <book>
+        <title>Advanced Programming in the Unix environment</title>
+        <source>www.amazon.com</source>
+        <price>65.95</price>
+    </book>
+    <book>
+        <title>Advanced Programming in the Unix environment</title>
+        <source>www.bn.com</source>
+        <price>65.95</price>
+    </book>
+    <book>
+        <title>TCP/IP Illustrated</title>
+        <source>www.amazon.com</source>
+        <price>65.95</price>
+    </book>
+    <book>
+        <title>TCP/IP Illustrated</title>
+        <source>www.bn.com</source>
+        <price>65.95</price>
+    </book>
+    <book>
+        <title>Data on the Web</title>
+        <source>www.amazon.com</source>
+        <price>34.95</price>
+    </book>
+    <book>
+        <title>Data on the Web</title>
+        <source>www.bn.com</source>
+        <price>39.95</price>
+    </book>
+</prices>

Logtalk/contributions/xml_parser/reviews.xml

@@ -0,0 +1,25 @@
+
+<reviews>
+ <entry>
+  <title>Data on the Web</title>
+  <price>34.95</price>
+  <review>
+               A very good discussion of semi-structured database
+               systems and XML.
+        </review>
+ </entry>
+ <entry>
+  <title>Advanced Programming in the Unix environment</title>
+  <price>65.95</price>
+  <review>
+               A clear and detailed discussion of UNIX programming.
+        </review>
+ </entry>
+ <entry>
+  <title>TCP/IP Illustrated</title>
+  <price>65.95</price>
+  <review>
+               One of the best books on TCP/IP.
+        </review>
+ </entry>
+</reviews>

Logtalk/examples/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/aliases/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/aliases/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/assignvars/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/assignvars/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/benchmarks/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/benchmarks/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/birds/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/birds/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/bricks/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/bricks/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/bricks/bricks.lgt

@@ -107,11 +107,11 @@
 
 
 :- object(stack_monitor,
-	implements(event_handlersp)).
+	implements(monitoring)).
 
 	:- info([
-		version is 1.0,
+		version is 1.1,
-		date is 1998/3/23,
+		date is 2006/12/14,
 		author is 'Paulo Moura',
 		comment is 'Monitor for brick movements printing an ascii representation of each brick position.']).
 

Logtalk/examples/classvars/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/classvars/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/dcgs/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/dcgs/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -112,22 +112,22 @@ yes
 
 % parsing URLs:
 
-| ?- url::parse("http://www.logtalk.org", Components).
+| ?- url::parse("http://logtalk.org", Components).
 
 Components = [protocol(http), address([www, logtalk, org]), path([]), file('')] 
 yes
 
-| ?- url::parse("http://www.logtalk.org/", Components).
+| ?- url::parse("http://logtalk.org/", Components).
 
 Components = [protocol(http), address([www, logtalk, org]), path(['']), file('')] 
 yes
 
-| ?- url::parse("http://www.logtalk.org/cvs", Components).
+| ?- url::parse("http://logtalk.org/cvs", Components).
 
 Components = [protocol(http), address([www, logtalk, org]), path([cvs]), file('')] 
 yes
 
-| ?- url::parse("http://www.logtalk.org/cvs.html", Components).
+| ?- url::parse("http://logtalk.org/cvs.html", Components).
 
 Components = [protocol(http), address([www, logtalk, org]), path([]), file('cvs.html')] 
 yes

Logtalk/examples/diamonds/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/diamonds/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/dynpred/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/dynpred/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/encodings/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/encodings/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/engines/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/engines/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/errors/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/errors/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/errors/warnings.lgt

@@ -25,7 +25,7 @@
 	% singleton variables in predicate clause
 	predicate(A) :-
 		write(C).
-	
+
 :- end_object.
 
 

Logtalk/examples/expansion/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/expansion/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/hello_world/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/hello_world/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/hooks/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/hooks/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/inheritance/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/inheritance/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/instmethods/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/instmethods/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lo/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lo/planner/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lo/planner/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lo/travellers/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lo/travellers/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/logic/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/logic/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lpa/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lpa/faults/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lpa/faults/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lpa/timetables/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/lpa/timetables/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/metainterpreters/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/metainterpreters/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -89,7 +89,7 @@ no
 
 % another example: expert system rules:
 
-| rules::prove(weather(Wheather)).
+| ?- rules::prove(weather(Wheather)).
 
 Wheather = raining 
 yes

Logtalk/examples/metainterpreters/rules.lgt

@@ -34,6 +34,8 @@
 	:- public([weather/1, weekday/1, time/1, goto/1]).
 	:- dynamic([weather/1, weekday/1, time/1, goto/1]).
 
+	:- dynamic(if/1).
+
 	:- op(200,  fx, if).
 	:- op(100, xfx, then).
 

Logtalk/examples/metapredicates/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/metapredicates/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -59,3 +59,30 @@ exit: sort([4,9],[4,9])
 Sorted = [1,2,3,4,9] ? 
 
 yes
+
+
+% call the meta-predicate apply/2 directly:
+
+| ?- meta::test_this.
+
+1, meta
+
+yes
+
+
+% send an apply/2 message to self:
+
+| ?- desc::test_self.
+
+2, desc
+
+yes
+
+
+% send an apply/2 message from another object:
+
+| ?- test::test_obj.
+
+3, test
+
+yes

Logtalk/examples/metapredicates/closures.lgt

@@ -0,0 +1,56 @@
+
+/*	Logtalk meta-predicates accept not only goals but also closures
+	as meta-arguments as illustrated in this example
+*/
+
+
+:- object(meta).
+
+	% the meta_predicate/1 directive below changes the interpretation of meta-calls on apply/2
+	% clauses; the integer argument ("1") implies that the first argument is a closure that will 
+	% be used to construct a goal by appending exactly one additional argument
+
+	:- public(apply/2).
+	:- mode(apply(+callable, ?term), zero_or_more).
+	:- meta_predicate(apply(1, *)).
+
+	apply(Closure, Arg) :-		% the Logtalk compiler verifies that any closure which is a
+		call(Closure, Arg).		% meta-argument is used within a call/N method that honors the
+								% meta-predicate directive (in this case, apply(1, *) => call/2)
+
+	:- public(test_this/0).		% simple predicate for testing calls to a local meta-predicate
+
+	test_this :-
+		apply(foo(X), Y),
+		write((X, Y)), nl.
+
+	foo(1, meta).
+
+:- end_object.
+
+
+:- object(desc,
+	extends(meta)).	
+
+	:- public(test_self/0).		% simple predicate for testing calls to a meta-predicate
+								% defined in an ancestor object
+	test_self :-
+		::apply(foo(X), Y),
+		write((X, Y)), nl.
+
+	foo(2, desc).
+
+:- end_object.
+
+
+:- object(test).
+
+	:- public(test_obj/0).		% simple predicate for testing calls to a meta-predicate
+								% defined in another object
+	test_obj :-
+		meta::apply(foo(X), Y),
+		write((X, Y)), nl.
+
+	foo(3, test).
+
+:- end_object.

Logtalk/examples/metapredicates/loader.lgt

@@ -1,13 +1,15 @@
 
 :- initialization(
-	logtalk_load(
+	logtalk_load([
-		[metapredicates])). 
+		closures,
+		metapredicates])). 
 
 /*
 If you intend to use the FOP XSL:FO processor for generating PDF documenting
 files, comment the directive above and uncomment the directive below
 
 :- initialization(
-	logtalk_load(
+	logtalk_load([
-		[metapredicates], [xmlsref(standalone)])).
+		closures,
+		metapredicates], [xmlsref(standalone)])).
 */

Logtalk/examples/mi/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/mi/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/miscellaneous/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/miscellaneous/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/modules/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/modules/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/msglog/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/msglog/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/operators/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/operators/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/parametric/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/parametric/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/points/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/points/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/polygons/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/polygons/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/profiling/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/profiling/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/profiling/message_counter.lgt

@@ -1,13 +1,13 @@
 
 :- object(message_counter,
-	implements(event_handlersp),
+	implements(monitoring),
 	imports(monitor)).
 
 
 	:- info([
-		version is 1.0,
+		version is 1.1,
 		author is 'Paulo Moura',
-		date is 1998/3/23,
+		date is 2006/12/14,
 		comment is 'Message counter monitor.']).
 
 

Logtalk/examples/profiling/stop_watch.lgt

@@ -1,13 +1,13 @@
 
 :- object(stop_watch,
-	implements(event_handlersp),
+	implements(monitoring),
 	imports(monitor)).
 
 
 	:- info([
-		version is 1.0,
+		version is 1.1,
 		author is 'Paulo Moura',
-		date is 1998/3/23,
+		date is 2006/12/14,
 		comment is 'Message executing time monitor.']).
 
 

Logtalk/examples/proxies/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/proxies/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/proxies/proxies.lgt

@@ -1,4 +1,7 @@
 
+% we use a parametric object in order to give an interpretation to an 
+% object proxy arguments and to encapsulate relevant predicates:
+
 :- object(circle(_Radius, _Color)).
 
 	:- public([

Logtalk/examples/puzzles/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/puzzles/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/reflection/NOTES.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/reflection/SCRIPT.txt

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.28.2
+Release 2.29.1
 
 Copyright (c) 1998-2006 Paulo Moura.  All Rights Reserved.
 =================================================================