RetroForth is a small, PublicDomain implementation of Forth. The latest version was inspired by cmForth, colorForth, eForth, and Pygmy. It also uses some of Chuck Moore's newer ideas.
The source code is clean and elegant. It has a small core, with most of the functionality being provided by optional modules.
As of 2008, RetroForth targets a portable virtual machine called Ngaro rather than running directly on the x86 CPU architecture.
Quick Links:
- Homepage, Downloads, and Documentation
- Mailing List
- IRC channel
Major Features:
- Small: binaries are 2-32k cells in size
- Small core written using a custom machine-forth cross-compiler
- Growing library of optional extensions providing new features and compatibility with other dialects of Forth
- Subroutine threading (stc) with select optimizations
- Actively developed and supported
- Simple, understandable source code
- It's released into the PublicDomain
- Support via email, forums, and IRC
- VM implementations in C, C#, Java, and JavaScript
MultiPlatformForth tries to classify Forth implementations by the language they were written in. Retro Forth is a bit hard to classify there. From an narrow point of view, it is written in an assembly language – the Ngaro VM, which has 30 instructions. From a wider point of view, since the Ngaro VM has several implementations including a C implementation and a JavaScript implementation ( http://rx-core.org/pages/?NgaroImplementations ), one could say that Retro Forth is written in C or one of those other implementation languages.
RetroForth has spawned or inspired several other Forth systems:
