Like many developers my age, the first programming language I ever used was BASIC. Specifically, GW-BASIC in a nice Epson "Abacus" XT machine with a green-on-black monitor back in primary school.
For me, the experience of writing my first program was magical. Having feedback from the computer with just few key strokes was an essential part of it.
10 PRINT "hola"
RUN
holaWriting a small/toy implementation of GW-BASIC may be a good exercise and a homage to this programming language. In the following posts I'm going to write about the ongoing experience of doing this.
As with other posts in this blog I'm going to try to write this program using a language I'm learning. For this task I'll be using Rust. Rust is a very interesting language with many concepts to learn. For me the only way of learning a new programming language is trying to use it to implement something.
The repo for work in this small project it's located here: https://github.com/ldfallas/rgwbasic .
The current implementation still lacks of most of the features to make it a useful (or usable) implementation. But at least you can write:
$ cargo run
...
Finished dev [unoptimized + debuginfo] target(s) in 0.05s
Running `target/debug/rgwbasic`
Ok
10 print "hello"
Ok
20 goto 10
Ok
run
"HELLO"
"HELLO"
"HELLO"
"HELLO"
"HELLO"
...