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copied!<p>I think I just completed my own challenge. I've added a second (optional) argument to the CLASS declaration macro for the superclass of the class being declared.</p> <p>My original implementation created a lot of inline junk around the constructor, so I decided to wrap some convenience functions up in a macro helper object to avoid redundancy.</p> <p>Here are the current incarnations of my class-like OOP macros:</p> <pre><code>// class-like oo #ifndef BASE #define BASE $$_ #endif #define COLLAPSE(code) code #define NAMESPACE(ns) var ns=BASE._ns(this).ns=new function() #define CLASS(c,__ARGS...) var c=[BASE._class(this),[__ARGS][0]]; \ new function() #define CTOR(c) BASE._extend($$_##c,c[1],this); \ c=c[0].c=$$_##c; function $$_##c #define PUBLIC(fn) BASE._public(this).fn=fn;function fn #define PRIVATE(fn) function fn #define STATIC(fn) BASE._static(this).fn=fn;function fn // macro helper object COLLAPSE(var BASE=new function(){ function Clone(){}; function clone (obj) { Clone.prototype=obj; return new Clone; }; function merge (sub, sup) { for (var p in sup) if (sup.hasOwnProperty(p)) sub[p]=sup[p]; }; this._extend = function (sub, sup, decl) { if (sup) { merge(sub, sup); sub.prototype=clone(sup.prototype); sub.prototype.constructor=sub; }; if (decl) { merge(sub.prototype, decl); decl._static=sub; decl._public=sub.prototype; }; }; this._static=this._ns=this._class=function (obj) { return (obj._static || obj); }; this._public=function (obj) { return (obj._public || obj); }; }) </code></pre> <p>... here's a test namespace ...</p> <pre><code>//#include "macros.js" NAMESPACE (Store) { CLASS (Cashier) { var nextId = 1000; this.fullName = "floater"; CTOR (Cashier) (fullName) { if (fullName) this.fullName = fullName; this.id = ++nextId; this.transactions = 0; } PUBLIC (sell) (item, customer) { this.transactions += 1; customer.inventory.push(item); } STATIC (hire) (count) { var newCashiers = []; for (var i=count; i--;) { newCashiers.push(new Cashier()); } return newCashiers; } } // Customer extends Cashier, just so we can test inheritance CLASS (Customer, Cashier) { CTOR (Customer) (name) { this.name = name; this.inventory = []; this.transactions = 0; } PUBLIC (buy) (item, cashier) { cashier.sell(this, item); } CLASS (Cart) { CTOR (Cart) (customer) { this.customer = customer; this.items = []; } } } } </code></pre> <p>... and here's the output ...</p> <pre><code>var $$_=new function(){ function Clone(){}; function clone (obj) { Clone.prototype=obj; return new Clone; }; function merge (sub, sup) { for (var p in sup) if (sup.hasOwnProperty(p)) sub[p]=sup[p]; }; this._extend = function (sub, sup, decl) { if (sup) { merge(sub, sup); sub.prototype=clone(sup.prototype); sub.prototype.constructor=sub; }; if (decl) { merge(sub.prototype, decl); decl._static=sub; decl._public=sub.prototype; }; }; this._static=this._ns=this._class=function (obj) { return (obj._static || obj); }; this._public=function (obj) { return (obj._public || obj); }; } var Store=$$_._ns(this).Store=new function() { var Cashier=[$$_._class(this),[][0]]; new function() { var nextId = 1000; this.fullName = "floater"; $$_._extend($$_Cashier,Cashier[1],this); Cashier=Cashier[0].Cashier=$$_Cashier; function $$_Cashier (fullName) { if (fullName) this.fullName = fullName; this.id = ++nextId; this.transactions = 0; } $$_._public(this).sell=sell;function sell (item, customer) { this.transactions += 1; customer.inventory.push(item); } $$_._static(this).hire=hire;function hire (count) { var newCashiers = []; for (var i=count; i--;) { newCashiers.push(new Cashier()); } return newCashiers; } } var Customer=[$$_._class(this),[Cashier][0]]; new function() { $$_._extend($$_Customer,Customer[1],this); Customer=Customer[0].Customer=$$_Customer; function $$_Customer (name) { this.name = name; this.inventory = []; this.transactions = 0; } $$_._public(this).buy=buy;function buy (item, cashier) { cashier.sell(this, item); } var Cart=[$$_._class(this),[][0]]; new function() { $$_._extend($$_Cart,Cart[1],this); Cart=Cart[0].Cart=$$_Cart; function $$_Cart (customer) { this.customer = customer; this.items = []; } } } } </code></pre> <p>Inheritance, internal classes, and nested namespaces seem to work fine. What do you think, is this a useful approach to class-like OOP and code reuse in js? Let me know if I've missed anything.</p>

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