export default function* sampler(wave) {
    let t1, v0, v1;
    [t1, v1] = wave[0]; // initial state
    let t = 0;
    for (let i = 1; i < wave.length; i++) {
        v0 = v1;
        [t1, v1] = wave[i]; // next change
        while (true) {
            if (t >= t1) {
                break;
            }
            t = yield v0;
        }
    }
    while (true) { // to the end of time
        yield v1;
    }
}