pony-tutorial VS zz

I don't think that there is a book written about Pony, but the tutorial and the list of patterns (WIP) are all you need to learn the language.

[Pony](https://tutorial.ponylang.io/): actors, reference capabilities, object capabilities.

Pony is a relatively young but interesting language with capabilities-security.

Well, depends on how you define ownership. Pony 's type system has reference capabilities which let you define who's allowed to do what to a reference and part of it sort of deals with ownership (along the lines of "this actor is allowed to do Y to the reference, other actors are allowed to do Z"). You can eg. have methods that return an isolated value that guarantees that there are no other references to that value, meaning it's automatically thread safe. You can also define things as vals which says that they are globally immutable, refs which give the current actor read/write capabilities but can't be shared with other actors

The alternatives are:

- Division must be impure (because it can throw an exception)

- Division must be partial - i.e. return Option[Int].

Both seem worse compared to defining division by zero as zero. Coq, Lean, and Pony do the same. https://github.com/ponylang/pony-tutorial/blob/master/conten...

There is this: https://github.com/zetzit/zz

You're right that you can't define a safe subset of C without making it practical. MISRA C defines a C subset intended to help avoid C's footguns, but it still isn't actually a safe language. There are alternative approaches though:

1. Compile a safe language to C (whether a new language or an existing one)

2. Formal analysis of C, or of some practical subset of C, to prove the absence of undefined behaviour

Work has been done on both approaches.

ZZ compiles to C. [0] Dafny can compile to C++, but it seems that's not its primary target. [1][2]

There are several projects on formal analysis of C. [3][4][5][6]

[0] https://github.com/zetzit/zz

[1] https://github.com/dafny-lang/dafny

[2] https://dafny-lang.github.io/dafny/

[3] https://frama-c.com/

[4] https://www.microsoft.com/en-us/research/project/vcc-a-verif...

[5] https://www.eschertech.com/products/ecv.php

[6] https://trust-in-soft.com/

Formal methods have been used successfully for decades; it's not just a pipe dream. Perfect software should ideally be something like ultra-low-defect software, though (that's the term the AdaCore folks use).

There are also other projects that aim to make formal software development much easier [0][1] and of course there's SPARK Ada.

[0] https://github.com/zetzit/zz

[1] https://github.com/dafny-lang/dafny

This post reminds me that I've been wanting to try out ZetZ[0]. It incorporates Z3 into a high-level programming language, and seems to do a lot of what the post talks about automatically.

[0] https://github.com/zetzit/zz

I still want to try the ZZ language (https://github.com/zetzit/zz) someday. It compiles to C, and uses a SMT solver to prove that you don't index out-of-bounds at compile time. But I don't like how it lacks generics, uses C idioms, and compiles to C.

The zz language uses a SMT solver to check for program soundness... I haven't tried it, but that's got to be more flexible and resource-hungry.

Especially the fact that it outputs C code. So interop is seamless.

https://github.com/zetzit/zz

For any systems language, interop with C is the litmus test.

With that in mind, this new language should not require 15,000 lines of standard library. A type-safe wrapper for libc should be enough...

You might find ZetZ interesting!