PySWIP 0.2.0 released

June 28, 2007

      I am pleased to announce the 0.2.0 version of PySWIP.

PySWIP is a GPL'd Python - SWI-Prolog bridge enabling to query SWI-
Prolog in your Python programs. It features an (incomplete) SWI-Prolog
foreign language interface, a utility class that makes it easy
querying with Prolog and also a Pythonic interface.

Since PySWIP uses SWI-Prolog as a shared library and ctypes to access
it, it doesn't require compilation to be installed.

Note that this version of PySWIP is slightly incompatible with prior
versions.

== Requirements ==

* Python 2.3 and higher.
* ctypes 1.0 and higher.
* SWI-Prolog 5.6.x and higher (most probably other versions will also
work).
* libpl as a shared library.
* Works on Linux and Win32, should work for all POSIX.

== News ==

* Prolog.query returns real Python datatypes.
* New Pythonic interface (See the last example).
* Several new examples, including Markus Triska's *Sudoku Solver*.
* Prolog module support.
* Foreign functions retrieve Python datatypes.

== Example (Using Prolog) ==

    >>> from pyswip import Prolog
    >>> prolog = Prolog()
    >>> prolog.assertz("father(michael,john)")
    >>> prolog.assertz("father(michael,gina)")
    >>> list(prolog.query("father(michael,X)"))
    [{'X': 'john'}, {'X': 'gina'}]
    >>> for soln in prolog.query("father(X,Y)"):
    ...     print soln["X"], "is the father of", soln["Y"]
    ...
    michael is the father of john
    michael is the father of gina

Since version 0.1.3 of PySWIP, it is possible to register a Python
function as a Prolog predicate through SWI-Prolog's foreign language
interface.

== Example (Foreign Functions) ==

    from pyswip import Prolog, registerForeign

    def hello(t):
        print "Hello,", t
    hello.arity = 1

    registerForeign(hello)

    prolog = Prolog()
    prolog.assertz("father(michael,john)")
    prolog.assertz("father(michael,gina)")
    list(prolog.query("father(michael,X), hello(X)"))

Outputs:
    Hello, john
    Hello, gina

Since version 0.2, PySWIP contains a 'Pythonic' interface which allows
writing predicates in pure Python.

== Example (Pythonic interface) ==

    from pyswip import Prolog, Functor, Variable, Query

    assertz = Functor("assertz", 2)
    father = Functor("father", 2)

    call(assertz(father("michael","john")))
    call(assertz(father("michael","gina")))

    X = Variable()
    q = Query(father("michael",X))
    while q.nextSolution():
        print "Hello,", X.value

Outputs:
    Hello, john
    Hello, gina

PySWIP homepage: http://code.google.com/p/pyswip
Downloads: http://code.google.com/p/pyswip/downloads/list
Subversion repo: http://pyswip.googlecode.com/svn/trunk
Discussion Group: http://groups.google.com/group/pyswip

Regards,

Yuce Tekol yucetekol [at] gmail [dot] com>