use typescript to check javascript types with jsdoc annotations

test.js

// check with tsc --allowJs --checkJs --noImplicitAny --noEmit --lib ES2017,dom test.js

/**
 * @param {Number} a operand 1
 * @param {Number} b operand 2
 * @return Promise<Number>
 */
async function add(a, b) {
  return a + b;
}


/**
@typedef Foo
@property {(n: Number) => void} bar
*/

/**
 * @param {Foo} foo
 */
function dofoo(foo) {
	foo.bar(5);
}
/**
 * @param {Object} options
 * @param {Number} options.c
 */
function printit({c}) {
	console.log(c);
}

(async function() {
	printit({c: await add(5, 3)});
})();