Summary
Leo is basically an outliner, and such a powerful one that it lends itself well to organizing all kinds of information hierarchically.
There are features that let you generate external files, in a structured fashion, based on the information contained in the outline.
It is written in pure Python, and extensible using Python.
If you use the outliner to store program code you can perform literate programming. There are a number of built-in features to support literate programming. (Leo itself is written in this style, using itself as the programming tool....)
Leo's document format is XML, so it is straightforward to process the content externally if there is a need.
Leo homepage has much more information.
Commentary
I am currently trying out literate programming techniques for the first time by writing one of the Python utilities for my project using Leo. So far, so good. The only thing that gets in the way are my traditional programming habits. DanEverhart - 2004/6/5
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