Factor/Interactive development

Factor has good support for Interactive development.

• Code can be loaded into a listener session
• Code can be reloaded: http://docs.factorcode.org/content/article-vocabs.refresh.html
• Tuple classes can be redefined, which updates instances: http://docs.factorcode.org/content/article-tuple-redefinition.html

A typical workflow with Factor involves an editor running concurrently with the UI. After making changes to a source file in the editor, you switch to the UI listener, and press F2, which runs the refresh-all word. This word reloads changed source files, at which point the changes can be tested interactively in the listener, or by running unit tests. The listener instance can remain running for a long time, with many such edit-reload cycles taking place in a single listener session.