rhai/benches/primes.rs

#![feature(test)]

///! Test evaluating expressions
extern crate test;

use rhai::{Engine, OptimizationLevel};
use test::Bencher;

// This script uses the Sieve of Eratosthenes to calculate prime numbers.

const SCRIPT: &str = r#"
let now = timestamp();

const MAX_NUMBER_TO_CHECK = 1_000;     // 168 primes <= 1000

let prime_mask = [];
prime_mask.pad(MAX_NUMBER_TO_CHECK, true);

prime_mask[0] = false;
prime_mask[1] = false;

let total_primes_found = 0;

for p in range(2, MAX_NUMBER_TO_CHECK) {
    if prime_mask[p] {
        total_primes_found += 1;
        let i = 2 * p;

        while i < MAX_NUMBER_TO_CHECK {
            prime_mask[i] = false;
            i += p;
        }
    }
}
"#;

#[bench]
fn bench_eval_primes(bench: &mut Bencher) {
    let mut engine = Engine::new();
    engine.set_optimization_level(OptimizationLevel::None);

    let ast = engine.compile(SCRIPT).unwrap();

    bench.iter(|| engine.consume_ast(&ast).unwrap());
}