Types

Ambient Declarations

                            
declare var document;
document.title = "Hello";  // Ok because document has been declared
                            
                        

Function Types

                            
function vote(candidate: string, callback: (result: string) => any) {
    // ...
}

vote("BigPig", function(result: string) {
    if (result === "BigPig") {
        // ...
    }
});
                            
                        

Interfaces

                            
interface Point {
    x: number;
    y: number;
}

function getX(p: Point) {
    return p.x;
}

class CPoint {
    constructor (public x: number, public y: number) { }
}

getX(new CPoint(0, 0));  // Ok, fields match
getX({ x: 0, y: 0, color: "red" });  // Extra fields Ok
getX({ x: 0 });  // Error: supplied parameter does not match
                            
                        

Classes and Inheritance

Classes and Inheritance

class BankAccount {
    constructor(public balance: number) {
    }

    deposit(credit: number) {
        this.balance += credit;
        return this.balance;
    }
}

class CheckingAccount extends BankAccount {
    constructor(balance: number) {
        super(balance);
    }

    writeCheck(debit: number) {
        this.balance -= debit;
    }
}

ES Harmony - Classes

class SkinnedMesh extends THREE.Mesh {
    constructor(geometry, materials) {
        super(geometry, materials);

        public identityMatrix = new THREE.Matrix4();
        public bones = [];
        public boneMatrices = [];
        ...
    }

    update(camera) {
        ...
        super.update();
    }
}

Modules

Modules

module M {
    var s = "hello";
    
    export function f() {
        return s;
    }
}

M.f();
M.s;  // Error, s is not exported

ES Harmony - Modules

module math {
    export function sum(x, y) {
        return x + y;
    }

    export var pi = 3.141593;
}