Factor

Factor (http://factorcode.org) is an expressive, fast and full-featured Concatenative language invented by Slava Pestov. The Factor implementation is released under a BSD license and runs on most common platforms.

Factor has been in development for more than five years, with a strong focus on practical programming all the way through; it began as a scripting language for a game. Factor has a small but friendly and vibrant community, and it is easy to learn.

• Binary packages are available from http://factorcode.org
• Why Factor?
• History
• Features
• Development
• Community

Documentation:

• Getting started
• Examples
• FAQ
• Documentation
• Coding Style
• Talks
• Screencasts

External resources:

• Wikipedia article about Factor
• Search: docs ; wiki ; factorcode.org ; comp.lang.factor.general , aka(?) factor-talk@sf (or via google); combined wiki+factorcode.org using gigablast .
• (There doesn't currently seem a way to search all three of wiki, factorcode, and list archive? Few search engines allow multi-site restrictions. Gigablast does, but doesn't index the gmane archive. It does mail-archive, but can't restrict it to "factor-talk", while leaving the other sites unrestricted. And its copy of docs.factorcode seems old or incomplete (no hits for "lambda"). The underlying problem with searching is "factor" as a language name. It has a very high rate of false positives on programming-related searches. For example, searching for "factor lambda" is useless compared to "python lambda" or "forth lambda". Or "factor call site optimization" vs "ruby call site optimization". This is crippling. But as the language name seems unlikely to change(?), the best we can do is search link kludges).