Compile-time execution

Constants

const MaxPlayers: usize = 64;

A constant declaration requires compile-time evaluation and an explicit type.

Dual-stage functions

const fn Double(Value: i32) -> i32 {
    return Value * 2;
}

const Answer: i32 = Double(21);

const fn is dual-stage: it can execute at compile time under the documented rules, or as an ordinary runtime call for runtime input.

Required compile-time calls

consteval fn requires every call to execute during compilation. Passing runtime-only input is an error.

Explicit forcing

const Expression explicitly requires compile-time evaluation. Array extents, enum discriminants, const-generic arguments, and typed attribute construction also require constant evaluation.

Restricted execution

Compile-time execution does not grant arbitrary I/O, environment access, allocation, FFI, or declaration-generation privileges. It is a bounded language facility, not a general build-script escape hatch.