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See theChange Log.

If you have SWI-Prolog installed, it's just:

pip install -U pyswip

SeeGet Started for detailed instructions.

PySwip is a Python-Prolog interface that enables queryingSWI-Prolog in your Python programs.It features an 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.

PySwip was brought to you by the PySwip community.Thanks to allcontributors.

• PySwip Home
• PySwip Documentation

frompyswipimportPrologProlog.assertz("father(michael,john)")Prolog.assertz("father(michael,gina)")list(Prolog.query("father(michael,X)"))== [{'X':'john'}, {'X':'gina'}]forsolninProlog.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

An existing knowledge base stored in a Prolog file can also be consulted, and queried.Assuming the filename "knowledge_base.pl" and the Python is being run in the same working directory, it is consulted like so:

frompyswipimportPrologProlog.consult("knowledge_base.pl")

frompyswipimportProlog,registerForeigndefhello(t):print("Hello,",t)hello.arity=1registerForeign(hello)Prolog.assertz("father(michael,john)")Prolog.assertz("father(michael,gina)")print(list(Prolog.query("father(michael,X), hello(X)")))

frompyswipimportFunctor,Variable,Query,callassertz=Functor("assertz",1)father=Functor("father",2)call(assertz(father("michael","john")))call(assertz(father("michael","gina")))X=Variable()q=Query(father("michael",X))whileq.nextSolution():print("Hello,",X.value)q.closeQuery()# Outputs:#    Hello, john#    Hello, gina

The core functionality ofProlog.query is based on Nathan Denny's public domain prolog.py.

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PySwip was used in scientific articles, dissertations, and student projects over the years.Head out toPySwip Community for more information and community links.

Do you have a project, video or publication that uses/mentions PySwip?file an issue or send a pull request.

If you would like to reference PySwip in a LaTeX document, you can use the providedBibTeX file.You can also use the following information to refer to PySwip:

• Author: Yüce Tekol and PySwip contributors
• Title: PySwip VERSION
• URL:https://pyswip.org

PySwip is licensed under theMIT license.