jsom.js

function loadFunction(){
	SP.SOD.executeFunc('SP.js', 'SP.ClientContext', getUsers);
}	

var getUsers = function () {
	var ctx = new SP.ClientContext.get_current();
	web = ctx.get_web();
	var users = web.get_lists().getByTitle('Users');
	var camlQuery = new SP.CamlQuery();


	camlQuery.set_viewXml('<View><Query><OrderBy><FieldRef Name=\'EmailAddress\'></FieldRef></OrderBy></Query><ViewFields><FieldRef Name=\'UserID\' /><FieldRef Name=\'EmailAddress\' /></ViewFields></View>');
	
	userItems = users.getItems(camlQuery);

	ctx.load(userItems);

	ctx.executeQueryAsync(function(){
			populateUserList()
		},
		function(sender,args){
				console.log(args.get_message())
		});
		
	}
	
var populateUserList = function () {
	var userEnumerator = userItems.getEnumerator();
	while (userEnumerator.moveNext()) {
		var ulItem = userEnumerator.get_current();
		var userID = ulItem.get_item("UserID");
		var email = ulItem.get_item("EmailAddress");
		console.log(userID + email);
	}
}

_spBodyOnLoadFunctionNames.push('loadFunction');