lodashAsyncTest.js

// Demonstrates to anyone who has any doubts that
// lodash remove() will not procede (i.e. execute
// synchronously) until it has a result.
var _ = require('lodash');

var x = [1,2,3,4,5,6,7,8,9];

console.log('a1: ' + a);

var a = _.remove(x, function(item){
	var r = delay();
	return item == 5;
});

console.log('a2: ' + a);

function delay() {
	var y = 0;
	for(var i=0; i<100000000; i++) {
		y += i;
	}
	return y;
}