One of the most 'interesting' issues in most garbage collectedlanguages is memory usage analysis: figuring out why your program isusing so much memory, and where. Often this winds up enmeshed intricky issues of object lifetime, retained references, and so on.

One of the first steps in this sort of work is simply figuring outwhat live objects you have in memory and what they are. Jonathan Ellis recently ran into this issue and wound up asking an interesting question: how do you get a list ofall

As editors web browsers have all sorts of problems, such as a narrowview of the text (squeezed into a small to tiny text box), only (very)basic editing operations, and a severe lack of features. Some of thefeatures can be somewhat fixed up by the website, like spellcheckingand saving drafts in progress, but even then they tend to be awkward.(You can read one person's grumbles about the problem in the contextof blogging here .)

This makes it puzzling that more

CQUEST 's workstations have a pieceof software that needs a read only 5+ gigabyte set of datafiles. Naturally we put the dataset on the local workstation disks,which works great. (These days it's hard to buy machines with lessthan 40 gigabyte disks, which leaves about 30 gigabytes free even witha generous Linux installation. We don't put user data on workstationsfor all the obvious reasons.)

However, every so often the dataset changes and we need to propagateall 5

To quote Glyph Lefkowitz (from here ):

Aah, the singleton. Global variables for the new millennium.

I'm not against global variables, but I am against misleading peopleabout them. The Singleton pattern lies about them; it looks like youhave a normal object, but you really have a global variable withoutknowing it.

(And if everyone knows you have a faux global variable, you are justtarting up a global variable in 'object-oriented' clothes. This islike respecting the letter of