Create a gist now

Instantly share code, notes, and snippets.

What would you like to do?
/**
Code copyright Dustin Diaz and Ross Harmes, Pro JavaScript Design Patterns.
**/
// Constructor.
var Interface = function (name, methods) {
if (arguments.length != 2) {
throw new Error("Interface constructor called with " + arguments.length + "arguments, but expected exactly 2.");
}
this.name = name;
this.methods = [];
for (var i = 0, len = methods.length; i < len; i++) {
if (typeof methods[i] !== 'string') {
throw new Error("Interface constructor expects method names to be " + "passed in as a string.");
}
this.methods.push(methods[i]);
}
};
// Static class method.
Interface.ensureImplements = function (object) {
if (arguments.length < 2) {
throw new Error("Function Interface.ensureImplements called with " + arguments.length + "arguments, but expected at least 2.");
}
for (var i = 1, len = arguments.length; i < len; i++) {
var interface = arguments[i];
if (interface.constructor !== Interface) {
throw new Error("Function Interface.ensureImplements expects arguments" + "two and above to be instances of Interface.");
}
for (var j = 0, methodsLen = interface.methods.length; j < methodsLen; j++) {
var method = interface.methods[j];
if (!object[method] || typeof object[method] !== 'function') {
throw new Error("Function Interface.ensureImplements: object " + "does not implement the " + interface.name + " interface. Method " + method + " was not found.");
}
}
}
};
@ghost

This comment has been minimized.

Show comment Hide comment
@ghost

ghost Jan 20, 2017

Thank you!

ghost commented Jan 20, 2017

Thank you!

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment