Parser Skeleton for FlatZinc
============================

This is the Gecode FlatZinc parser and interpreter, stripped of all
Gecode-specific stuff. You can use it as a starting point for your own
FlatZinc interpreter.

This is version 1.0, released 2011-01-17.

If you have questions, don't hesitate to contact me by email: tack@gecode.org

The copyright and license information is listed in the header of each file.

Guido Tack, 2011

Implementing solver-specific methods
------------------------------------

In order to hook up your solver to the parser, look at the file flatzinc.hh.
It contains a class FlatZincModel, which is implemented in flatzinc.cpp. It
defines a number of methods that you have to implement, e.g. methods that
create variables, that post constraints, or that run the actual search.

All these methods are marked with TODO comments and an output on stderr. Just
search for these comments and make the necessary changes.

The actual constraint posting is done in the file registry.cpp. You have to
add a posting function for each constraint you want to implement, and register
it with the corresponding flatzinc name (see the examples in the file).

Compilation
-----------

Compile the *.cpp files using your favorite C++ compiler (tested with gcc 4.2
and Microsoft Visual C++ 2008). If you want to rebuild the lexer and parser
from the sources, you need flex (version 2.5.33 or better) and bison (version
2.3 or better), and run the following commands:

flex -olexer.yy.cpp lexer.lxx
bison -t -o parser.tab.cpp -d parser.yxx

If you want to use the parser as a library, link the object code from all .cpp
files except fz.cpp with you own code. The file fz.cpp contains a main method
that constructs a parser and executes a FlatZinc program, so you can use this
to get a standalone executable.

The code archive contains a Makefile that should build the standalone fz
executable on any platform where a recent version of gcc and make are
installed.

Changelog
---------

1.0 (2010-01-17)
Initial release.

1.1 (2010-01-18)
Added missing includes to enable compilation with gcc >= 4.3. Added sample
Makefile.

1.2 (2012-03-09) for FlatZinc 1.4
Fixed some bugs in the parser and lexer, and updated to latest FlatZinc spec.

1.3 (2012-03-19) for FlatZinc 1.5
Removed code from the parser that has become redundant because of changes in
the FlatZinc spec. Empty domains for int variables no longer cause an error,
but have to be handled by the solver.