I have a number of JavaScript "classes" each implemented in its own JavaScript file. For development those files are loaded individually, and for production they are concatenated, but in both cases I have to manually define a loading order, making sure that B comes after A if B uses A. I am planning to use RequireJS as an implementation of CommonJS Modules/AsynchronousDefinition to solve this problem for me automatically.
Is there a better way to do this than to define modules that each export one class? If not, how to you name what the module exports? A module "employee" exporting a class "Employee", as in the example below, doesn't feel DRY enough to me.
define("employee", ["exports"], function(exports) {
exports.Employee = function(first, last) {
this.first = first;
this.last = last;
};
});
define("main", ["employee"], function (employee) {
var john = new employee.Employee("John", "Smith");
});
The AMD proposal allows you to just return a value for the exported object. But note that is a feature of the AMD proposal, it is just an API proposal, and will make it harder to translate the module back to a regular CommonJS module. I think that is OK, but useful info to know.
So you can do the following:
I prefer modules that export a constructor function to start with an upper-case name, so the non-optimized version of this module would also be in Employee.js
define("Employee", function () {
//You can name this function here,
//which can help in debuggers but
//has no impact on the module name.
return function Employee(first, last) {
this.first = first;
this.last = last;
};
});
Now in another module, you can use the Employee module like so:
define("main", ["Employee"], function (Employee) {
var john = new Employee("John", "Smith");
});