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crumb: Logic Programming
A tutorial on logic programming in Pyke, including *statements*,
*pattern matching* and *rules*.
section-pages: , statements, pattern_matching/index, rules/index, plans
Logic Programming Tutorial
Pyke is an inference engine that applies rules_ to facts_ to establish
additional facts (through forward-chaining_ rules), and/or to prove *goals*
and optionally assemble Python functions
into customized call graphs, called plans_ (through backward-chaining_ rules).
Pyke may then be reset_, deleting the last set of facts, so that the cycle
may be repeated. For each cycle a different rule base may be activated_.
The plan_ capability allows the postponement of code execution until the
top-level goal has been completely proven. This shields the code from
blind alleys and the backtracking_ that occurs within the rules.
Once a plan_ has been created, it may be executed multiple times with different
arguments. It may also be pickled_, and later run again only requiring one
small Pyke module.
Pyke also provides an end user question_ capability, as well as the capability
to run commands_ on the local system to guide the inferencing.