forth

>You don't write README.md, ARCHITECTURE.md, JavaDocs, etc, at all? Maybe? Not sure - haven't worked on enough big projects to declare answer >A new developer is supposed to go through all the codebases and figure out for himself? Yes to this bit - code should have very clear structure to it with appropriate comments attached, whether that's literate style as JonesForth<https://github.com/phf/forth/blob/master/x86/jonesforth.S> shows, small section header comment or whatever. It should be very clear what section exploring does - tiny example but cat<http://9p.io/sources/plan9/sys/src/cmd/cat.c> from plan 9 very simple segmented code - deals with file opening in main loop and cat function just reads and prints text

You're very welcome. For later exploration, JonesForth <https://github.com/phf/forth/tree/master/x86> is excellent exploration of Forth's internals. There were quite a few Forth stories a month or so ago if want more resources.

One of the simplest interpreters that also has a compiler built-in is Forth. It is somewhat heretical to conventional computer science but it can be fully understood top to bottom by normal humans due to it features or lack thereof. :) A quick search found this repository of JonesForth which is a literate programming version of a Forth system that describes the code as it goes along. There appears to be source for various targets. https://github.com/phf/forth It is a very interesting exercise that shows you a kind of bare minimum requirement way to make a language and provides insights for what is missing to build more conventional languages.

Reasonable means the simplest and most minimal set of instructions to implement a particular behavior. These are your Primitives for the intermediate language. If you find something that you can't do in terms of the existing instructions, then the required operation should be added to your set of primitives. A good way to figure some of this out is to read through a minimal FORTH, say something like Jones FORTH (https://github.com/phf/forth/tree/master/x86 here's at least one port). The core set of primitives is in the .S assembly file and everything else is implemented in terms of those 'words'. If you want a really simple one, look up something like https://esolangs.org/wiki/Brainfuck and work your way up into a more reasonable (i.e. actual numbers!) ISA.

Kind of a bunch of work, but at the same time it'd be an interesting learning exercise. There have been ports to quite different architectures, such as PPC and ARM, and one you can run on baremetal RPi: http://www.lshift.net/blog/2007/10/04/jonesforth-ported-to-p... https://github.com/M2IHP13-admin/JonesForth-arm https://github.com/phf/forth https://github.com/organix/pijFORTHos