parser VS gleam

I have mixed feelings on Rust's syntax, especially around generics, lifetimes, and the `modifier -> keyword` syntax (i.e. `async fn` or `pub fn`). For Inko, I wanted something that's easy to parse by hand, and no context specific parsing (e.g. `QUOTE -> something` being the start of a lifetime in one place, but a char literal in another place).

Another motivator for that is that years ago I worked on Rubinius for a while (an implementation of Ruby), and helped out with a parser for Ruby (https://github.com/whitequark/parser). The Ruby developers really liked changing their already impossible syntax in even more impossible ways on a regular basis, making it a real challenge to provide syntax related tools that support multiple Ruby versions. I wanted to avoid making the same mistake with Inko, hence I'm actively trying to keep the syntax as simple as is reasonable.

As for the specific examples:

- `fn async` means your parser only needs to look for `A | B | fn` in a certain scope, instead of `A | B | fn | async fn`. This cuts down the amount of repetition in the parser. An example is found at https://github.com/inko-lang/inko/blob/8f5ad1e56756fe00325a3..., which parses the body of a class definition.

- Skipping parentheses is directly lifted from Ruby, because I really like it. Older versions took this further by also letting you write `function arg1 arg2`, but I got rid of that to make parsing easier. It's especially nice so you can do things like `if foo.bar.baz? { ... }` instead of `if foo().bar().baz?()`, though I suspect opinions will differ on this :)

- Until recently we did in fact use `::` as a namespace separator, but I changed that to `.` to keep things consistent with the call syntax, and because it removes the need for remembering "Oh for namespaces I need to use ::, but for calls .".

- `[T]` for generics is because most editors automatically insert a closing `]` if you type `[`, but not when you type `<`. If they do, then trying to write `10<20` is annoying because you'd end up with `10<>20`. I also just like the way it looks more. The usual ambiguity issues surrounding `<>` (e.g. what leads to `foo::()` in Rust) doesn't apply to Inko, because we don't allow generics in expressions (i.e. `Array[Int].with_capacity(42)` isn't valid syntax) in the first place.

So there was this really awesome gem called parser written by someone not on the core team that gives you a super clean understanding of the Ruby code. Not only does it not care if the parentheses are there or not, but there's a really well structured and precise mapping of where the information comes from and it is completely semantic. So if you've got parentheses or not, it's not gonna make any difference in the structure of your abstract syntax tree, but you can actually ask where are the locations. That is taken care of, but the understanding of the code, what's going on in the code is completely independent of if you wrote those parentheses or not.

Working with those things, possibly with the help of reading books, tends to be how it's learned I'd say. I'm not the one you asked, but I personally worked with Ruby for 10 years, worked on a system to improve coverage reports, which relied on rewriting ruby code. Doing so was done using the Parser gem, which is a ruby parser that has a different abstract syntax tree (https://github.com/whitequark/parser). I'm also interested in programming languages development, so I try to read on this / develop my own language in my free time.

Changes like this have been going on for years. I remember that back when I was still helping out with https://github.com/whitequark/parser, the author on a regular basis had to deal with Ruby making yet more non-trivial syntax changes. IIRC they eventually burned out on the project because of that, but my memory is a bit fuzzy.

This is more a function of Ruby than of tree-sitter. The tree-sitter grammars for other languages are hopefully less inscrutable. For Ruby, we basically just ported whitequark's parser [1] over to tree-sitter's grammar DSL and scanner API.

[1] https://github.com/whitequark/parser

I haven't had time to really try to write anything in it, but https://gleam.run/ looks really good too. Like Elm for backend + frontend!

Want a friendly language for building safe systems at scale? Gleam is here for you. It features modern and familiar syntax, that's reliable and scalable. Gleam runs on an Erlang virtual machine, and can run plenty of concurrent tasks. It comes with a compiler, build tool, formatter, editor integrations, and package manager all built in so you can get started right away. Congrats to the team on shipping your first major version 🙌.

While I love Clojure, I have to agree about tooling. I recently started using Gleam* and was impressed at how easy it was to get up and running with the CLI tool. I think this is an important part of getting people to adopt a language.

* https://gleam.run/

If you use languages that compile to WASM (such as Gleam https://gleam.run), and can also run Postgres via WASM, then it opens very interesting offline scenarios with codebases which are similar on both the client and the server, for instance.

Recently, Gleam has gained more popularity, and a lot of developers (including me) are learning it. At the time of this writing, it has exceeded 14k stars on GitHub; it grew really fast for the last month.

Oh, strange that github had a date of 2016 on this one: https://github.com/gleam-lang/gleam/issues/2

I was just going by that, though I do remember checking out gleam 5 years ago or so.

Re: macros, I really do think they’re a big deal and all the other newer languages I’ve used, such as Rust have some kind of macros or powerful meta programming features.

For older languages, a few, like Ruby have enough meta programmability to make nice DSLs, but many others don’t. Given the choice, I’d much rather have Elixir/Clojure style macros than other meta-programming facilities I’ve seen so far.

I had been only following this language with some interest, I guess this was born in gitlab not sure if the creator(s) still work there. This is what I'd have wanted golang to be (albeit with GC when you do not have clear lifetimes).

But how would you differentiate yourself from https://gleam.run which can leverage the OTP, I'd be more interested if we can adapt Gleam to graalvm isolates so we can leverage the JVM ecosystem.