Confused about Classes, Instances and Methods in ColdFusion - oop

Question

My question is probably best illustrated with an example. In javascript I'm used to being able to do stuff like this:
// create a simple class
function myClass() {
this.attr_example = "attribute";
}
myClass.prototype.do_something = function() {
return "did something";
}
// create an instance of it, and modify as needed
var thing = new myClass();
thing.myMethod = function(arg) {
return "myMethod stuff";
}
// ... so that this works as expected
console.log(thing.myMethod());
console.log(thing.do_something());
console.log(thing.attr_example);
When it comes to doing something similar in ColdFusion, I get stuck. I constantly find myself wanting to do things like this:
<cfscript>
// thing.cfc contains a normal cfcomponent definition with some methods
var thing = createObject("component","Thing");
function formattedcost() {
return "#LSCurrencyFormat(this.cost)#";
}
thing.formattedcost = formattedcost;
</cfscript>
<cfoutput>
#thing.formattedcost()#
</cfoutput>
Let's assume that for this question, it doesn't make sense to add "formattedcost" as a method on the Thing class because it is purely presentational. Let's also assume that simply using #LSCurrencyFormat(thing.cost)# in the <cfoutput> tags wont suffice either because we need the instance of Thing to be evaluated by a templating system (mustache in this case). Even further, I'd like to avoid having to create another .cfc file just to extend my Thing class to add a couple of methods.
What can I do? Is this style of programming possible in ColdFusion?

Answer 1

Yes you can do this:
Thing.cfc
<cfcomponent output="false" accessors="true">
<cfproperty name="cost" type="numeric">
<cffunction name="init" output="false" access="public"
returntype="any" hint="Constructor">
<cfargument name="cost" type="numeric" required="true"/>
<cfset variables.instance = structNew()/>
<cfset setCost(arguments.cost)>
<cfreturn this/>
</cffunction>
</cfcomponent>
test.cfm
<cfscript>
// thing.cfc contains a normal cfcomponent definition with some methods
thing = new Thing(725);
function formattedcost() {
return "#LSCurrencyFormat(getCost())#";
}
thing.formattedcost = formattedcost;
</cfscript>
<cfoutput>
#thing.formattedcost()#
</cfoutput>
Result
$725.00