Archive for December, 2009
Last time I began covering linked lists in AS3. As anyone who has ever taken a data structures class can tell you, this is definitely a core data structure. As such, it has numerous benefits compared to other single-dimensional data structures like arrays and hash tables. The Array class in AS3 is far from a C/C++ array, which is simply a contiguous block of memory. AS3’s Array class blurs the lines between arrays, linked lists, and hash tables. So as I implement a linked list class in AS3 it is quite interesting to see how the normal pros and cons change. I’ve expanded on the LinkedList class I started last week and done some more preliminary performance testing. Read on to see the updates.
Today’s article is inspired by Jean-Philippe Auclair’s excellent article on arrays and the comment he recently posted on my article about map performance. In it he discusses how the Array class is implemented using a densely-packed C/C++ array (a contiguous block of memory) and, after the first undefined element, a hash table. This got me thinking of three questions, together the subject of today’s article. First, when an Array‘s densely-packed portion is split using the delete operator, how fast is this? Secondly, can it be re-joined? Third, how fast is rejoining it?
On the heels of last Friday’s article on Utility Functions For Objects, today’s article will show a few utility functions for the Class class. In case you’re not familiar with it, Class represents a class like you would write and is useful main for more dynamic programming where you want to instantiate a class based on a variable (eg. var c:Class) rather than a constant (eg. BitmapData). So how do you get a Class variable? The Flash API provides some ways to go about it and I’ll provide some ways to make that more convenient.
Like most programmers writing non-trivial applications, I’ve piled up a lot of utility functions over the years. Most of them are simple and effective. They are short and get their job done. You or someone you know has probably written these functions, but maybe not in AS3. So today I’m going to share a few utility functions for Objects in AS3.