When I was in high school I wrote a nice FORTH for the TRS-80 Color Computer using the OS-9 operating system which was a Unix-like multitasking OS that would fit on a 6809 microcomputer.
I think it was around 2000 lines of assembly code to implement most of the FORTH-83 standard although mine was unusual in that it did not support the block-based I/O that was common on “language system” FORTHs but instead it had handle-based API for accessing files similar to Unix, C and MS-DOS in version 2 and up.
The programming environment was a lot like Linux overall in that I’d use an ed or vi clone to edit files, then run something like an assembler or C compiler. I’d run my FORTH binary and it would present an interactive environment like most FORTHs.
I think it was around 2000 lines of assembly code to implement most of the FORTH-83 standard although mine was unusual in that it did not support the block-based I/O that was common on “language system” FORTHs but instead it had handle-based API for accessing files similar to Unix, C and MS-DOS in version 2 and up.
The programming environment was a lot like Linux overall in that I’d use an ed or vi clone to edit files, then run something like an assembler or C compiler. I’d run my FORTH binary and it would present an interactive environment like most FORTHs.