Prolog DCGs: Clean Grammar Specification and Practical Testing
A concise guide to using Prolog DCGs for clean grammar specification, with a worked example, testing tips, and performance considerations.
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prologProlog DCGs: Use --> for readable parsers but keep the difference-list contract visible
DCGs give Prolog a readable --> syntax for context-free parsers, but they compile to predicates with two extra difference-list arguments. Keep the In/Out contract visible to avoid silent mis-parses and infinite loops.
Turning Recursive Prolog into a Memoized Powerhouse with Tabling
Discover how Prolog’s tabling feature turns recursive problems like Fibonacci into fast, memoized computations. Learn to enable tabling in SWI‑Prolog, benchmark the speedup, inspect table statistics, and understand the memory trade‑offs.
Solving Sudoku with CLP(FD) in SWI-Prolog: A Practical Constraint Modeling Guide
Model Sudoku as a constraint problem in SWI-Prolog with CLP(FD): domains, all_distinct constraints, first-fail labeling, and how to check and debug the result.
Tabling in Prolog: Caching Results to Stop Infinite Recursion
Learn how Prolog’s tabling caches results to stop infinite recursion, see a simple example, and understand its memory trade‑offs.
Stop Writing Generate-and-Test Loops: CLP(FD) in SWI-Prolog
Replace blind generate-and-test loops with SWI-Prolog's CLP(FD): state integer constraints declaratively, let propagation prune the search, and tune labeling strategies separately from your model.
Solving Puzzles with CLP(FD) Constraints in SWI-Prolog: Domains, Posting, and Labeling
A practical workflow for CLP(FD) in SWI-Prolog: declare finite domains, post constraints that propagate, label solutions with search strategies like first-fail, and diagnose residual goals and infeasibility.