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                <script type="text/js-worker">
    async function sha256(message) {
        // encode as UTF-8
        const msgBuffer = new TextEncoder('utf-8').encode(message);

        // hash the message
        const hashBuffer = await crypto.subtle.digest('SHA-256', msgBuffer);

        // convert ArrayBuffer to Array
        const hashArray = Array.from(new Uint8Array(hashBuffer));

        // convert bytes to hex string
        const hashHex = => b.toString(16).padStart(2, '0')).join('');
        return hashHex;

    self.addEventListener('message', async function (e) {
        const hash = await sha256(;
    }, false); 

    <input type="text">
    <span>Text to hash</span>


                @use postcss-nested;
@use postcss-cssnext;

body {
    background: #002F47;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100vh;
    flex-flow: column nowrap;
    font-family: "Roboto", sans-serif;

label {
    position: relative;
    & span {
        position: absolute;
        top: 0;
        display: block;
        color: #A9CEB7;
        font-size: 1.5rem;
        margin-bottom: 0.5rem;
        text-transform: uppercase;
        font-weight: 700;
        opacity: 0.5;
        transform: translatey(calc(-100% - 5px));

input {
    border: 5px solid #1C7F81;
    box-shadow: 0 5px 5px rgba(0, 0, 0, 0.5);
    padding: 1rem;
    border-radius: 5px;
    font-size: 2rem;
    outline: none;
    &:active {
        border-color: #289B80;
        & + span {
            opacity: 1;

output {
    color: #91DCC5;
    padding: 25px;
    font-size: 3rem;
    word-wrap: break-word;
    font-family: 'Roboto Mono', monospace;


                const { createStore, compose, applyMiddleware } = Redux;
const { runSaga, eventChannel } = ReduxSaga;
const { call, take } = ReduxSaga.effects;

const reducer = ()=>({});
const sagaMiddleware = ReduxSaga.default();
const store = createStore(reducer, {}, compose(
store.runSagas =;

// ------------ Worker

function createWorker(){
    const scripts = Array.from(document.querySelectorAll('script[type="text\/js-worker"]'));
    const blob = new Blob( script => script.textContent),
        {type: 'text/javascript'}
    const url = window.URL.createObjectURL(blob);
    return new Worker(url);

// ------------ Sagas

function createWorkerChannel(worker) {
    return eventChannel(emit => {

        const onMessage = (event) => emit(;
        worker.addEventListener('message', onMessage, false);
        const unsubscribe = () => worker.terminate();
        return unsubscribe

function* outputHash(hash){
    const node = yield call([document, 'querySelector'], 'output');
    node.textContent = hash;

function* addListeners(worker){
    const node = yield call([document, 'querySelector'], 'input');
    node.addEventListener('input', (e)=> worker.postMessage(;

function* initialize(){
    const worker = yield call(createWorker);
    const channel = yield call(createWorkerChannel, worker)
    yield call(addListeners, worker);
        const payload = yield take(channel);
        yield call(outputHash, payload);

// ------------ Run