ctql — Compile-Time Query Language (for types)

Header-only C++23 toolkit to filter/partition/sort/reduce types using user-defined keys (like sizeof(T), alignof(T), or your own compile-time metric). Also includes tiny ct_string helpers and nicer concept/predicate wrappers.

• Single header: #include <ctql/ctql.hpp>
• Standard: C++23
• Compiler: Clang++ 18 (tested)

---

Examples

For examples see here.

---

Why ctql?

• Treat type packs like a queryable dataset: partition, sort, reduce at compile time.
• Bring your own key: KeyOf<T> → size (e.g., sizeof, alignof, wire size, priority).
• Zero runtime cost. Great for metaprogramming, registries, ECS layouts, SBO/MTU policies.

---

Install

Just drop the ctql/ folder in your include path.

clang++-18 -std=c++23 -Wall -Wextra -pedantic demo.cpp -Ipath/to/ctql

#include <ctql/ctql.hpp>
using namespace ctql;

---

Notes

• Works with any “size” metric you provide: sizeof, alignof, protocol bytes, priorities, etc.
• Sorting uses a pivot-partition strategy; equals go to the “right” bucket by default (deterministic, not stable).
• Everything is constexpr/type-level; no runtime overhead.