Although I've been programming in Python for a few years now, it keepssurprising me with little bits and pieces. Here's a neat Python languagefeature that I recently used for the first time (discovered originallythrough Bram Cohen's LiveJournal).

A common programming pattern is 'search for a something to work on, butstop if you don't find anything'. In Python one might write it somethinglike this (taken more or less from DWiki 's source):

found = False

Every HTTP reply from a web server can include a Last-Modified: header, which theoretically tells interested parties when the web pagewas last modified. This is really something that works best when theweb server is just sending out static files; when it is generatingdynamic content, like DWiki does, things get interesting.

The major use of Last-Modified: is to decide when a browser already hasa current copy of the web page and doesn't need to fetch it again. Thus,with dynamic pages

Honesty compels me to admit that part of why I am trying blogging isthat I coded a bunch of blog features into DWiki , my wiki-thing, and Iwould feel kind of stupid if they never got used. (The blogdir codehas a clear usage case, but the blog code does not quite so much.)

But that's not all of it. Web pages cry out for a linking structure,an organization, a taxonomy, just like we are supposed to sensiblyorganize directories on our computers

DWiki is the software that runs CSpace , including this blog . It'swound up much bigger than I expected and wanted it to be. This is sortof the story of how (or why) that happened.

DWiki started out with a simple goal: serve up (revision controlled)wiki-text documentation as HTML pages. It didn't have to edit thepages; we'd do that in a real editor in a real environment. The coreprogram model was simple: pages would be generated