Patternia Documentation¶

A modern C++ pattern matching DSL

Patternia is a modern C++ pattern-matching DSL designed to make dispatch logic clear, expressive, and type-safe - without sacrificing performance or compilation efficiency.

Navigation¶

Start Here¶

• Getting Started - Minimal examples and core syntax
• Installation - How to integrate Patternia into your project

Concepts and Tutorials¶

• From Control Flow to Pattern Matching - Onramp for new users
• Pattern Matching in Other Languages - Mapping familiar ideas to Patternia
• Custom Predicate Guards - Guard design and composition

Worked Examples¶

• Policy Constraint Matching - Declarative rules and access control
• Geometric Constraint Matching - Numeric constraints as patterns

Reference¶

• API Documentation - Complete API reference for all patterns and functions
• Performance Notes - Algorithm evolution and dispatch strategy by version
• Design Overview - Semantics and matching model

Project Information¶

• Releases - Version update history
• Benchmark Scripts - JSON compare and visualization tooling

System Requirements¶

• C++ Standard: C++17 or later (floating-point val<V> literals need C++20)
• Compilers (minimums enforced by cmake/CheckCompilerVersion.cmake):

• Tested in CI: GCC 11/13 and Clang 14/16/18 on Linux (C++17 through C++26); MSVC and clang-cl on Windows (C++20 through C++26).

Benchmarking¶

• Run benchmark suite from project root:

.\build\bench\ptn_bench.exe --benchmark_filter="Variant" --benchmark_out=build/variant_all.json --benchmark_out_format=json

• Visualize one JSON across implementations:

py -3 scripts/bench_single_report.py --input build/variant_all.json --include "Variant" --outdir build/bench/single --prefix variant_single