20161113 - Vintage Programming 2


This is a follow-up to the 20140816 - Vintage Programming post talking about this,


Retrospective
Was thinking about resurecting the Atom project now that Vulkan supports what I would need to complete it, and had to decide upon what language to write the reboot in. Looking back at all my language and compiler experiments on PC over the years, the A Language as described in that prior post from 2014 had the most utility and was the easiest to be productive on in current PC style operating systems.

Adjustments
First implementation of compiler took ANSI text source file and output a binary. The source had to build the ELF or PE header for the binary (similar to an assembler running without a linker). This round, the compiler is the platform executable, and programs will run directly from source (JITing themselves). Compiler will be built around interactive run-time edit/recompile/retry loop which maintains existing program state in memory during the process.


Source can thus be edited in the background in any text editor while the program runs. Save the source file, and the program reloads itself while it runs. Likewise the source could be edited inside the program itself. Lots of flexibility.

Portability and Distribution
One source file for any platform, source adapts to the platform as it JITs itself into binary code at run-time. Distribution is just pairing the platform specific compiler binary (which can be renamed to the program name), and the source file (which will have a set name like "rom.a", so a double click of the renamed compiler runs the application without any arguments). Platform specific compilers will be a few K executable depending on how minimal the ELF or PE is. For a secondary option at some point I'll make something which can build a single executable with the compiler embedded with source.

Open Source
I'm going fully open-source for this project. Compiler is being written in NASM assembly with embedded PE/ELF so there is no need for any kind of linker to build the compiler. Thus far got a 1st draft on the PE done with all the Kernel32 symbols I believe I need, with an executable which loads and then spins forever. Will continue to bring up on Windows first to verify PE works on real Windows boxes, before migrating back to Linux and Wine. More later as this project continues ...

Work in progress here: github.com/TimothyLottes/A