Factor is a concatenative programming language designed and implemented by Slava Pestov.
Factor's main influences are Joy, FORTH, and Lisp.
Some of its key features include:
- Postfix syntax
- Dynamic typing
- Dynamic scoping
- Primary compound data types are linked lists, vectors, and namespaces (lists of name/value pairs)
- Rich math library including floating point, ratios, complex numbers
- Continuations
- Integrated HTTP server
- Focus on interactive and test-driven development
There are two implementations of Factor:
- an interpreter/compiler written in Java
- a (somewhat incomplete) interpreter written in C