To borrow your video game analogy. F* is the dwarf fortress of programming languages. Screenshots are only going to confuse anyone who isn't ready to take a significant mental journey.
This is needless fearmongering. F* looks a lot like F# code with semantics you should be familiar with if you've worked with other proof oriented languages. The website design is dated is all. The book gives exactly what the OP wants in the introductory chapter.
I'm the opposite: when landing in a programming language site I want to know the user case the authors had in mind, the memory model, the type system, the compilation targets, the data layout, the control structures, and only at the end just check that the syntax is not indentation based.
Indentation based is a pain when copy-pasting between contexts with different indentation levels, as you have to fix it up manually, which is error-prone. In languages without it, you can just auto-format. (And even in an editor that doesn't support that, having a second indicator makes it less error-prone to fix manually)
No indeed I'm not a fan. I find it brittle and arbitrary for data values especially; that also makes automatic code generation and edition harder, for no good reason.
But that's not an important consideration either way.
For what it's worth, I love the semantics of many indentation based languages (F# for example) but really dislike editing them. Visually scanning is much easier with braces (imo) and it's much easier to navigate braced languages when using a vim-like editor
I don't mind indentation based languages. I used to hate them, but they've grown on me after using python, Haskell, Idris, Agda, etc. And I ended up making my own language indentation based (it is similar to Idris).
That said, it is hard-mode:
- You'll have to figure out how to parse it.
- If you want editor support, it's a pain to get tree-sitter to handle it.
- You may not be able to pull off editor operations like "rename" without implementing a pretty printer (a rename might affect indentation).
I think it is helpful for crude error recovery. On parse error, my language will simply skip to the next column 0 token and parse another declaration.
I did not do this (hindsight), but I would recommend arranging the grammar so you only get indented blocks in cases where the previous line ends in a keyword that introduces it. I think python has a trailing `:` every time indentation is introduced, and
Elm does this too - in statements like `let` you need a newline after the `let` to get the multi-declaration version. (This addresses the rename issue.)
and click on the image below the text "You probably want to read it while trying out examples and exercises in your browser by clicking the image below.".
In the section of (1) also the PDF version is linked:
I wonder why more languages don't have a few simple examples of: "HTTP server", "hello world", "todo list app" that you can just click and it shows the code for how you'd make it in that language.
It matters a lot how the syntax looks IMO and seeing how, say, an API is scaffolded, helps understand a lot about the language in one glance
Edit: Page 18 of the PDF. That's the first time I found what the code looks like, thanks for sharing!
> I wonder why more languages don't have a few simple examples of: "HTTP server", "hello world", "todo list app" that you can just click and it shows the code for how you'd make it in that language.
Often the reason is that the value that the programming language brings is thinking very differently about how to write code - the examples how to write something in it are merely the "more boring" consequences of this different way of thinking.
--
If you want a programming language that "just" enables you to write something well-understood (in particular in the area of web development) like your suggested
> "HTTP server", "hello world", "todo list app"
in a perhaps just a little bit more elegant/concise way, just look at which web development language/framework is currently fashionable on HN.
I imagine the quick project showcase would be different for Swift or for Rust.
Would be nice to have something like that for this Fstar or any language I haven’t heard of - or maybe have but never looked into so I see why people are using it.
Like what kinds of things i can even think of writing with it - an implementation example
> I imagine the quick project showcase would be different for Swift or for Rust.
> Would be nice to have something like that for this Fstar or any language I haven’t heard of - or maybe have but never looked into so I see why people are using it.
I suggest simply having a look at the table of contents of
This in my opinion gives you a first rough idea for what kind of problems people are using F*.
Spoiler alert: these are not the kind of problems which are related to ["HTTP server", "hello world", "todo list app", ...].
This is exactly the reason why I wrote further above:
> Often the reason [why more languages don't have a few simple examples of: "HTTP server", "hello world", "todo list app"] is that the value that the programming language brings is thinking very differently about how to write code - the examples how to write something in it are merely the "more boring" consequences of this different way of thinking.
The OP doesn't want encompassing, they want the following example from the tutorial on the front page:
type vec (a:Type) : nat -> Type =
| Nil : vec a 0
| Cons : #n:nat -> hd:a -> tl:vec a n -> vec a (n + 1)
let rec append #a #n #m (v1:vec a n) (v2:vec a m)
: vec a (n + m)
= match v1 with
| Nil -> v2
| Cons hd tl -> Cons hd (append tl v2)
This is a completely reasonable thing to want and expect.
Idk why languages don't have their syntax in a sandbox front-and-center on the home page.
It's like a video game site with zero screenshots or videos (also rampant).
New programming languages I want 2 things:
1. What does the syntax look like
2. Why would I use this language
Talk about the proof logic, show the syntax, thank you
I think rixed means "code editing" (I guess that rixed is simply not a native (L1) or excellent L2 English speaker).
That said, it is hard-mode:
- You'll have to figure out how to parse it.
- If you want editor support, it's a pain to get tree-sitter to handle it.
- You may not be able to pull off editor operations like "rename" without implementing a pretty printer (a rename might affect indentation).
I think it is helpful for crude error recovery. On parse error, my language will simply skip to the next column 0 token and parse another declaration.
I did not do this (hindsight), but I would recommend arranging the grammar so you only get indented blocks in cases where the previous line ends in a keyword that introduces it. I think python has a trailing `:` every time indentation is introduced, and Elm does this too - in statements like `let` you need a newline after the `let` to get the multi-declaration version. (This addresses the rename issue.)
Perhaps English is not a native language for zlsa?
But I clicked one (1) link to the online book and found a thousand?
FYI: The link to this tutorial is unluckily a little bit obscured on the F* website: Go to
> https://fstar-lang.org/index.html#learn (1)
and click on the image below the text "You probably want to read it while trying out examples and exercises in your browser by clicking the image below.".
In the section of (1) also the PDF version is linked:
> https://fstar-lang.org/tutorial/proof-oriented-programming-i...
But I do see the editor to try it.
I wonder why more languages don't have a few simple examples of: "HTTP server", "hello world", "todo list app" that you can just click and it shows the code for how you'd make it in that language.
It matters a lot how the syntax looks IMO and seeing how, say, an API is scaffolded, helps understand a lot about the language in one glance
Edit: Page 18 of the PDF. That's the first time I found what the code looks like, thanks for sharing!
Often the reason is that the value that the programming language brings is thinking very differently about how to write code - the examples how to write something in it are merely the "more boring" consequences of this different way of thinking.
--
If you want a programming language that "just" enables you to write something well-understood (in particular in the area of web development) like your suggested
> "HTTP server", "hello world", "todo list app"
in a perhaps just a little bit more elegant/concise way, just look at which web development language/framework is currently fashionable on HN.
See, by listing those, you can tell what it is.
I imagine the quick project showcase would be different for Swift or for Rust.
Would be nice to have something like that for this Fstar or any language I haven’t heard of - or maybe have but never looked into so I see why people are using it.
Like what kinds of things i can even think of writing with it - an implementation example
> Would be nice to have something like that for this Fstar or any language I haven’t heard of - or maybe have but never looked into so I see why people are using it.
I suggest simply having a look at the table of contents of
> https://fstar-lang.org/tutorial/proof-oriented-programming-i...
This in my opinion gives you a first rough idea for what kind of problems people are using F*.
Spoiler alert: these are not the kind of problems which are related to ["HTTP server", "hello world", "todo list app", ...].
This is exactly the reason why I wrote further above:
> Often the reason [why more languages don't have a few simple examples of: "HTTP server", "hello world", "todo list app"] is that the value that the programming language brings is thinking very differently about how to write code - the examples how to write something in it are merely the "more boring" consequences of this different way of thinking.
Ok, what kinds of problems are they?
And ideally - what does a simple solution look like in F-star?
Set me on the path to installing the thing (ideally above the fold)
Examples provide more than syntax. It's the semantics that we care about most.
... and this semantics is explained in a quite encompassing way in the introductory notes "Proof-Oriented Programming in F*":
> https://fstar-lang.org/tutorial/proof-oriented-programming-i...
> https://fstar-lang.org/tutorial/
Is this used in the industry ? And for what kind of software ?
https://www.microsoft.com/en-us/research/blog/everparse-hard...
https://lwn.net/Articles/770750/
https://project-everest.github.io/
Does it get basic stuff like subtraction and u8 right, unlike Lean?
> No, it isn't.
https://fstar-lang.org/ claims otherwise:
"F* (pronounced F star)".