> The only thing I would suggest is always prefering [[ to [ because it makes dealing with parameter expansions much more easier.

I wrote the article before Bash 3 was released, and the article remains appropriate for platforms that don't have Bash 3 abilities. If you read down in the article, you will see where I address this issue:

http://arachnoid.com/linux/shell_programming.html#Bash_Versi...