Python CFFI bindings for the ‘C’ Language Integrated Production System CLIPS 6.30.

Initially developed at NASA’s Johnson Space Center, CLIPS is a rule-based programming language useful for creating expert and production systems where a heuristic solution is easier to implement and maintain than an imperative one. CLIPS is designed to facilitate the development of software to model human knowledge or expertise.

CLIPSPy brings CLIPS capabilities within the Python ecosystem.

CLIPSPy comes as a wheel for most of the Python versions and architectures. Therefore, it can be installed from Pip.

> pip install clipspy

CLIPS 6.30 is available as Debian package in Unstable.

# apt install libclips libclips-dev
# pip install clipspy

The provided Makefile takes care of retrieving the CLIPS source code and compiling the Python bindings together with it.

$ make
# make install

The following tools are required to build the sources.

• gcc
• make
• wget
• unzip
• python
• python-cffi

The following conditional variables are accepted by the Makefile.

• PYTHON: Python interpreter to use, default python
• CLIPS_SOURCE_URL: Location from where to retrieve CLIPS source code archive.
• SHARED_LIBRARY_DIR: Path where to install CLIPS shared library, default /usr/lib

from clips import Environment, Symbol

environment = Environment()

# load constructs into the environment
environment.load('constructs.clp')

# assert a fact as string
environment.assert_string('(a-fact)')

# retrieve a fact template
template = environment.find_template('a-fact')

# create a new fact from the template
fact = template.new_fact()

# implied (ordered) facts are accessed as lists
fact.append(42)
fact.extend(("foo", "bar"))

# assert the fact within the environment
fact.assertit()

# retrieve another fact template
template = environment.find_template('another-fact')
fact = template.new_fact()

# template (unordered) facts are accessed as dictionaries
fact["slot-name"] = Symbol("foo")

fact.assertit()

# execute the activations in the agenda
environment.run()