REXML is an XML processor for the language Ruby. REXML is conformant (passes 100% of the Oasis non-validating tests), and includes full XPath support. It is reasonably fast, and is implemented in pure Ruby. Best of all, it has a clean, intuitive API. This software is distribute under the Ruby license.

Why REXML? There, at the time of this writing, already two XML parsers for Ruby. The first is a Ruby binding to a native XML parser. This is a fast parser, using proven technology. However, it isn't very portable. The second is a native Ruby implementation, and as useful as it is, it has (IMO) a difficult API. I have this problem: I dislike obfuscated APIs. There are several XML parser APIs for Java. Most of them follow DOM or SAX, and are very similar in philosophy with an increasing number of Java APIs. Namely, they look like they were designed by theorists who never had to use their own APIs. The extant XML APIs, in general, suck. They take a markup language which was specifically designed to be very simple, elegant, and powerful, and wrap an obnoxious, bloated, and large API around it. I was always having to refer to the API documentation to do even the most basic XML tree manipulations; nothing was intuitive, and almost every operation was complex. Then along came Electric XML.