Дмитрий Беляев

class deferred {
  constructor() {
    this.promise = new Promise(resolve => this.resolve = resolve);
  }

  then(f) {
    this.promise = this.promise.then(f);
  }
}

class deferred {
  constructor() {
    this.callbacks = [];
  }

  then(f) {
    this.callbacks.push(f);
  }

  resolve(val) {
    this.callbacks.reduce((res, f) => f(res), val);
  }
}

SSH will fail to start if there are syntax errors in the /etc/ssh/sshd configuration file. The command following command will tell you if any directives are incorrect:
/usr/sbin/sshd -T
If the configuration test does not return any errors, I would suggest starting sshd in debugging mode, this will provide you with a detailed startup of the service:
/usr/sbin/sshd -ddd

$date_registration = array('name' => $name, 'password' => $password);
$sth = $pdo->prepare("INSERT INTO users (name, password) VALUES (:name, SHA(:password))");
$sth->execute($date_registration);
// --
$_SESSION['user_id'] = $pdo->lastInsertId();

Для чего служат подобные вызовы и что конкретно в них проиходит?

category.id === this.$route.params.category

var lol = {
  salary: 15,
  bonus: 100,
  gen: 'girl',
  get total() {
     return this.salary + this.bonus;
   }
}

console.log(lol.total);

var lol = {
  salary: 15,
  bonus: 100,
  gen: 'girl',
  getTotal() {
     return this.salary + this.bonus;
   }
}

console.log(lol.getTotal());

if (Math.abs(175 - rost) < 5) { /* средний рост*/ }

if ((175 - rost) * (175 - rost) <  5 * 5) { /* средний рост*/ }