promiseihateyounode.js

function doReplacePromise() {
	const input = 'haha';
	const result = input.replace(/a/g, function() {
		let result;
		myPromiseFunc()
			.then(function(data) {
				result = data;
			});
		
		return result;
	});
	
	console.log(result);
};

function myPromiseFunc(cb) {
	return new Promise(function(resolve, reject) {
		resolve('e');
	});
}

doReplacePromise();