I had to design a simple general purpose language for university, so I tried creating "ZoomerScript" with Jetbrains MPS

prof@infosec.pub to Programmer Humor@programming.dev – 507 points –

Insert <it's not much but it's honest work> meme. It only supports ints and bools, some logic and simple arithmetics and it compiles to Java but damn was it hard to get that far.

Can you guess what everything does?

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It only supports ints and bools, some logic and simple arithmetics and it compiles to Java but damn was it hard to get that far.

I have a bachelor’s in computer science and I don’t think I would be able to do that…

Compiler courses are typically master level.

My college must have been full of sadists. They had undergrad compiler courses and required students to take them.

Same, it usually whacked about half the attempted majors into another major. In the first half of senior year. They kept wondering why their program wasn't growing much even though similar colleges' programs were growing like mold on a dorm shower curtain. I enjoyed the course and never used the primary skills taught in it again.

It really depends on what you do, but somehow, I actually did end up using some of the things those courses were teaching. It turns out the visitor pattern is extremely useful for writing JavaScript code transformers.

I had an entry-level compiler course during undergrad. We used JavaCC to generate a lexer and parser based on eBNF grammar.

Im having a mandatory compiler course on my 3rd year of (french) bachelor

I definitely read this as you were a third year French major being forced to taking a compiler course for a moment and went wtf. Then my brain slapped itself and realized you mean you're a student in France.

Haha yeah I meant that I was studying computer science im France and not studying french. Here in France, bachelor are called licence and are only 3 years compared to 4 in north america afaik, but there are way fewer electives

Nah, I think they’ve won the French version of The Bachelor 2 years in a row and are about to win the third.

It was part of my BSc, but that was over 20 years ago.

Compilers are a specialized topic - and syntax design is fiddly - but it really is no harder than any other sort of program. A lot of the hard theoretical work was done back in the sixties and seventies. You don't have to start from scratch. These days it's "only" a matter of implementing the features you want and making sure your syntax doesn't leave itself open to multiple interpretations. (just as arithmetic, e.g. '5 × 4 - 1' requires some rules to make sure there's only one correct interpretation, so do language syntaxes need to be unambiguous to parse. )

Don't get me wrong - writing a language is a lot of work and it's super cool that OP has done this! I just want to stress that language development is 100% doable with an undergrad degree. If you understand recursion and how to parse a string you already have all the theory you need to get started.

Valuable input! I actually am an undergrad student. There are a lot of frameworks out there that support writing languages, with MPS being one of them.

If I'd start from scratch again and had a little more time, I'd frankly try writing an interpreter myself, instead of trying to conform to weird framework syntax, which I won't be able to reuse in any other context.

Saying syntax design is fiddly is an understatement. I focused very hard on getting an abstract syntax somehow finished before working on generation in my first iteration. Then I had so much technical debt, that I couldn't get anything to work and had to rewrite a lot. So I scrapped it all and started again, starting with top level concepts including generation and only implementing some lower level ones, once everything around it worked properly.

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It’s likely transpiring and not compiling, so it’s a lot easier than it seems. Source: made a language that adds features to Python and transpiles to valid Python.

It doesn't compile or transpile in actuality. It generates Java based on an abstract syntax tree. The concrete syntax is not considered in Java generation by MPS.

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