Snoweb lets you interactively edit noweb literate programming files in xemacs. Snoweb lets you contextually switch between tangled and untangled views of the document with a single keystroke, and your edits take effect in the noweb documentation regardless of which view you are in. This means you can use it the way you really edit code, rather than the way you'd write code if you had photographic memory and emitted perfect code from the start.
