error not-comptime

What it means#

const initialisers, associated constants, array lengths and attribute arguments MUST be comptime expressions (§4.1, §4.9, §15.1): literals, other constants and calls to comptime functions. Ordinary functions, and anything with effects, cannot run at compile time.

Example#

fn compute() -> i32 => 6 * 7

const ANSWER: i32 = compute()      // <- not-comptime

not-comptime

How to fix#

comptime fn compute() -> i32 => 6 * 7

const ANSWER: i32 = compute()

Mark the function comptime (it must then be deterministic and free of effects), or write the value directly.

See also#

• comptime-error
• atomic-effects