----- Original Message -----
> From: Alex Kleider <aklei...@sonic.net> > To: tutor@python.org > Cc: > Sent: Thursday, June 19, 2014 8:10 PM > Subject: Re: [Tutor] Tips > > On 2014-06-18 18:37, Steven D'Aprano wrote: >> Python tries very hard to ensure that every module is loaded only once. >> (There are circumstances where you can fool it, but they're rare.) >> Since >> the module holds state (variables) and behaviour (functions), modules >> perform the same sort of role as classes, so a module which is loaded >> once is very similar to a singleton instance. In other words, if you >> want a class to implement singleton behaviour, you have to work at it. >> But if you shift the functionality from the class into a module, Python >> gives you singleton behaviour for free. >> >> But if you're not sure why anyone would want a singleton instance, I >> agree with you: most (but not all) uses of singletons are unnecessary. > > The idea of a singleton class is new to me as is this comparison of > class vs module. > Can anyone suggest a place to turn for more discussion of the topic? > thks, alexK Maybe this (it's about Singleton and Borg): http://stackoverflow.com/questions/1318406/why-is-the-borg-pattern-better-than-the-singleton-pattern-in-python _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
