Rule based programming

Python projects

• https://github.com/blurg/sauron-engine

All others are dead :()

• https://github.com/nemonik/Intellect (Dead - 2017)
• https://github.com/jruizgit/rules (dead)
• https://github.com/cmaclell/py_rete (dead)
• https://github.com/nilp0inter/experta (dead)
• https://github.com/GNaive/naive-rete (dead)
• https://github.com/jhgg/hyrule/ (dead prototype)

Other technologies

• CLIPS
• https://www.evrete.org/ (Java)

Mockup API In Python

See: https://www.evrete.org/guides/run/prime-numbers/

from dataclasses import dataclass


def main():
    service = KnowledgeService()
    knowledge = service.new_knowledge(
        "PYTHON-CLASS",
        RuleSet
    )

    # Init subject and its known properties
    fritz = Subject(croaks=True, eats_flies=True)

    # Insert Fritz and fire all rules
    knowledge.new_stateless_session().insert_and_fire(fritz)

    # Fritz should have been identified as a green frog
    print("Is Fritz a frog?\t", fritz.is_frog)
    print("Is Fritz green? \t", fritz.is_green)

    service.shutdown()


@dataclass
class Subject:
    croaks: bool = False
    eats_flies: bool = False
    is_frog: bool = False
    is_green: bool = False


class RuleSet:
    @staticmethod
    def rule1(ctx, s):
        if s.is_frog and not s.is_green:
            s.is_green = True
            ctx.update(s)

    @staticmethod
    def rule2(ctx, s):
        if s.croaks and s.eats_flies and not s.is_frog:
            s.is_frog = True
            ctx.update(s)


# Alt

@rule
@where({"$s.is_frog", "!$s.is_green"})
def rule1(ctx, s):
    s.is_green = True
    ctx.update(s)


@rule
@where({"$s.croaks", "$s.eats_flies", "!$s.is_frog"})
def rule2(ctx, s):
    s.is_frog = True
    ctx.update(s)


#
# Framework
#
class KnowledgeService:
    def new_knowledge(self, name, rule_set_class):
        return Knowledge(rule_set_class)

    def shutdown(self):
        pass


class Knowledge:
    def __init__(self, rule_set_class):
        self.rule_set_class = rule_set_class

    def new_stateless_session(self):
        return StatelessSession(self.rule_set_class)


class StatelessSession:
    def __init__(self, rule_set_class):
        self.rules = [rule_set_class.rule1, rule_set_class.rule2]

    def insert_and_fire(self, subject):
        ctx = RhsContext()
        for rule in self.rules:
            rule(ctx, subject)


class RhsContext:
    def update(self, subject):
        pass


if __name__ == "__main__":
    main()

#dataclass

Page last modified: 2024-12-09 23:29:05