Question

So in actionscript 3, instances of the Object class can be used an as associative array:

var doNotHaveSexWith:Object = new Object();
doNotHaveSexWith['mum'] = new Person(...);
doNotHaveSexWith['dad'] = new Person(...);
doNotHaveSexWith['dave'] = new Person(...);

Say I have some class, and one of it’s members is a read only ‘Object’ which contains my collection of people.

I think code readability takes a major hit if I return this ‘Object’, as how would the programmer know what to do with it?
The only way someone is going to know that it is a collection is if they read the code or the comments…

What’s the best way to signal that an Object is a collection, rather than a simple object?

Options:

• Create a dynamic class, simply
  extending from Object, called
  “AssociativeArray” or something, just
  so the code becomes more readable…

• Use something like the AS3
  Datastructures Library, though this
  seems like a bit of overkill.

• Just append the word Collection to
  the end of the variable name?

For example:

var hotPeopleCollection:Object = new Object();
hotPeopleCollection['me'] = new Person(...); 
hotPeopleCollection['sandrasully'] = new Person(...);

What do you think?

Update: I’ve decided to go with a custom class extending Dictionary. This way I can wrap a sensible access function around the searching function: hasOwnProperty and give the class a meaningful name.

I chose Dictionary over Object for two reasons:

1. Dictionary makes more intuitive sense for a collection
2. Dictionary appears to perform at O(1) for searching. See this fairly
   informal dictionary vs array vs object performance benchmark

Answer 1

Use a dictionary.

http://livedocs.adobe.com/flash/9.0/ActionScriptLangRefV3/flash/utils/Dictionary.html

You can still use a string for your key, or any object for that matter.

var dict:Dictionary = new Dictionary();
var obj:Object = new Object();
var key:Object = new Object();
key.toString = function() { return "key" }

dict[key] = "Letters";
obj["key"] = "Letters";

dict[key] == "Letters"; // true
obj["key"] == "Letters"; // true 
obj[key] == "Letters"; // true because key == "key" is true because key.toString == "key"
dict["key"] == "Letters"; // false because "key" === key is false
delete dict[key]; //removes the key

A lot of developer ( myself included ) will tell you: Never use an Object. You are basically blindfolding your compiler. Always either use a built in datatype or make your own. Now obviously you didn’t know about dictionaries in this case, but as a general rule, if you think you want to use a plain old Object datatype, think again.

Update:

Another link you might find helpful:

http://www.gskinner.com/blog/archives/2006/07/as3_dictionary.html