I seriously hope I don't have to describe to you the plethora of perils encountered when using global variables. Bugs are notoriously difficult to track down and the code generally devolves into a mess.
That said, selective usage of global variables can often be a big benefit to a program's maintainability. For example, most session implementations in web applications are glorified global variables. Using a sessionstore can significantly reduce the amount of tramp data that goes on the URL.
Often, specific variables are maintained globally, such as $dbh. With proper documentation, I don't see a problem with this. I would (and do) prefer using a singleton instead of an explicit global, just so that new usages can be easily added. But, styles differ.
Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose
I shouldn't have to say this, but any code, unless otherwise stated, is untested
In reply to Re: Global variable vs passing variable from sub to sub