{purejs}

Create a constructor ...

var MyConstructor = Pure.constructor.create(function () {
      // This is the constructor.
      // Here is where we initialize the instance.
      // All instance-level members are defined here.
    },{
    // Here is where we define prototype-level members.
});

Create a constructor inheriting a prototype ...

var MyOtherConstructor = Pure.constructor.create(function () {
      // Call the base constructor.
      MyConstructor.call(this);
    }, {
    // Empty prototype members.
}, MyConstructor.prototype);

Create a constructor inheriting a prototype, but cache the base prototype ...

var MyOtherConstructor2 = (function(base) {
    return Pure.constructor.create(function () {
        // Call the base constructor.
        base.call(this);
      }, {
      // Empty prototype members.
    }, base.prototype);
}(MyConstructor));

Create a constructor inheriting a constructor's prototype ...

var MyOtherConstructor3 = (function(base) {
    return Pure.constructor.create(function () {
        // Call the base constructor.
        base.call(this);
      }, {
      // Empty prototype members.
    }, base); // You can pass a constructor function directly not just objects
}(MyConstructor));

Ensure an object has a specific interface ...

var Rect = Pure.constructor.create({
    init: function(w, h) {
        this._width = w;
        this._height = h;
    },
    width: function(value) {
        if (arguments.length === 1) this._width = value;
        return this._width;
    },
    height: function(value) {
        if (arguments.length === 1) this._height = value;
        return this._height;
    }
});

var r = {
    width: 40,
    height: 40
};

var rect = Rect(10, 10);

// true since all objects adhere to their own interface.
Pure.adheresTo(r, r);

// false since width and height are not functions and init is not present.
Pure.adheresTo(r, Rect.prototype);
// false since width and height are not functions and init is not present
// and _width and _height are not present.
Pure.adheresTo(r, rect);

// true since we test r against an interface specification.
Pure.adheresTo(r, {
    width: 'number',
    height: 'number'
});

// true since we test r against an interface specification with
// the 'any type' specifier for both width and height.
Pure.adheresTo(r, {
    width: '*',
    height: '*'
});

Copy all own properties from one object to another ...

var a = {name: 'a'}, b = {name: 'b', sex: 'm'};
// Copy all own properties from 'b' into 'a',
// overwriting properties with the same name.
// The result: a={name: 'b', sex: 'm'}
Pure.mixin(a, b);

Copy all own properties from many objects to another ...

var a = {name: 'a'}, b = {name: 'b', sex: 'm'}, c = {name: 'c', age: 29};
// Copy all own properties from 'b' and 'c' into 'a',
// overwriting properties with the same name.
// The result: a={name: 'c', sex: 'm, age: 29'}
Pure.mixin(a, b, c);

Test if an object is an array ...

var a = [], b = new Array(), c = {}, d = 1;
Pure.isArray(a); // true
Pure.isArray(b); // true
Pure.isArray(c); // false
Pure.isArray(d); // false

Get the true type of an object ...

var a = null, b = [], c = 3, d = {}, e = 'hello world', f = new Number(34);
Pure.typeOf(a); // 'null'
Pure.typeOf(b); // 'array'
Pure.typeOf(c); // 'number'
Pure.typeOf(d); // 'object'
Pure.typeOf(e); // 'string'
Pure.typeOf(f); // 'object'

Intelligently check the type of an object ...

var a = 1, b = new Number(1), c = 'hello', d = new String('hello');
Pure.isNumber(a); // true
Pure.isNumber(b); // true
Pure.isString(c); // true
Pure.isString(d); // true