Building a BASIC compiler from scratch targetting .NET Core (v3) using VB.NET.
In the past I've built a 100% language-compatible version of the classic GW-BASIC MS-DOS environment. It was made available through Windows Phone and as a SilverLight web-hosted application. (Man, I really picked two "winners" there...)
The GW-BASIC project was built mostly through "brute force" without any thought to making the project (code) publically visible. As such, I've never released the code.
Fast forward a few years to now...
The original GW-BASIC project was the classic/retro "IDE" and an interpreter (REPL). This project is going to take this all in a very different direction by starting with the compiler as the ultimate goal. I'm sure that some of the original project will make it's way into this one... but for the most part, this project is "starting from scratch" with the ultimate goal of having a pretty good representation of "classic" BASIC targetting .NET Core!
For now, yes, I'm planning on adding support for line numbers. ;-)
Why not?
So far I've worked through the all of the available episodes of the video series (see below)... until that series gets to the point of actually compiling to .NET (Core) I will be following along pretty closely with what is being done in Minsk. Once we reach the compile milestone is when I plan to incorporate the work I did in my GW-BASIC project into the structure of this project; ultimately compiling to an executable.
As I already stated, much of the work on this project will be "borrowed" from my previous work; however, I'm also borrowing (learning) from Immo Landwerth's video series on the subject of "building a compiler". He's not claiming to be a "master"; however, he's certainly has more knowledge on the subject than I do and a good amount of experience on Roslyn (and .NET) that I feel I can definately learn from and am treating his video series as a sort of "master class" on the subject. ;-)
Although not the same compiler, as I said the process of building this compiler is inspired in part by Minsk by Immo Landwerth (YouTube). If you are interested in how to build a C-style compiler for .NET, please see his video series. Some key differences are:
- A language similar to BASIC instead of C/JScript.
- Using Visual Studio 2019 Community Edition (instead of Visual Studio Code).
- Using GitHub Tools for Visual Studio instead of command line tools.
I highly recommend Immo's video series... it's awesome!
You can also find the repo for Immo's version here.
One additional note is that although not inspired by the comment he has at about 11 minutes into his first video, this project does attempt to answer the request someone made in his first live stream. ;-)