https://github.com/dlang/dmd/pull/17044

It's enabled with -preview=safer

It enables "safe by default". This is different from marking functions as @safe, in that:

1. it does not mark the function as @safe, the function mangling does not change

2. it enables all @safe checks except it does not complain about calling @system functions

3. it does not interfere with attribute inference

In other words, it does not impose transitive safety. You can still call malloc() and printf() in it.

Once it appears in the next release, I encourage people to add -preview=safer to their build process.

On Thursday, November 28, 2024 12:08:29 AM MST Walter Bright via Digitalmars- d-announce wrote:
> https://github.com/dlang/dmd/pull/17044
>
> It's enabled with -preview=safer
>
> It enables "safe by default". This is different from marking functions as @safe, in that:
>
> 1. it does not mark the function as @safe, the function mangling does not change
>
> 2. it enables all @safe checks except it does not complain about calling @system functions
>
> 3. it does not interfere with attribute inference
>
> In other words, it does not impose transitive safety. You can still call
> malloc() and printf() in it.
>
> Once it appears in the next release, I encourage people to add -preview=safer to their build process.

So, essentially, it makes functions with no explicit @safety attributes be somewhere between @system and @safe by disallowing language constructs which are considered @system but not disallowing calling @system functions.

- Jonathan M Davis

Right.

On Thursday, 28 November 2024 at 21:01:30 UTC, Walter Bright wrote:
> Right.

11 languages have coroutine support natively

Only 1 with full borrow semantics : rust.

That according to chatgpt

Please sir , the coroutine dips is still at 1st draft.

While other dip will make lines fewer , their execution still from top down.

The coroutine, is a game changer. That will make porting  library from other languages straightforward.

On 29/11/2024 10:30 AM, f wrote:
> On Thursday, 28 November 2024 at 21:01:30 UTC, Walter Bright wrote:
>> Right.
> 
> 11 languages have coroutine support natively
> 
> Only 1 with full borrow semantics : rust.
> 
> That according to chatgpt
> 
> Please sir , the coroutine dips is still at 1st draft.
> 
> While other dip will make lines fewer , their execution still from top down.
> 
> The coroutine, is a game changer. That will make porting  library from other languages straightforward.

I'll be restarting on my language design work, including coroutines next year.

I'm taking a few months where I work on my own stuff.

I have not forgotten any of the design work :)

On Thursday, 28 November 2024 at 21:30:33 UTC, f wrote:
> On Thursday, 28 November 2024 at 21:01:30 UTC, Walter Bright wrote:
>> Right.
> The coroutine, is a game changer. That will make porting  library from other languages straightforward.

People mostly with C99 and C++(who even touch 20th standard, right?) experience will answer: we have core.thread and std.concurrency for years.. this is enough, what else do you want? :P

On Thursday, 28 November 2024 at 07:08:29 UTC, Walter Bright wrote:
> https://github.com/dlang/dmd/pull/17044
>
> It's enabled with -preview=safer

For writing memory safe code, this is a more practical engineering approach. Fortunately, this compilation option will reduce the number of times @safe annotation is used and the code will be relatively cleaner.

On Thursday, 28 November 2024 at 07:08:29 UTC, Walter Bright wrote:
> https://github.com/dlang/dmd/pull/17044
>
> It's enabled with -preview=safer

This is pretty cool!

But I've noticed it shows errors for ImportC code:

> lib\gen-blend2d-windows\blend2d.c(207,45): Error: cast from `int` to `void*` not allowed in safe code

Is there a bug report for it?

On Thursday, 28 November 2024 at 07:08:29 UTC, Walter Bright wrote:
> https://github.com/dlang/dmd/pull/17044
>
> It's enabled with -preview=safer
>

I think this is going to still cause issues with dependencies, which might just be a dub problem but I'm not sure.

For example I've tried to add `dflags `-preview=safer` to my dub.sdl and now I get errors from 3rd party libraries:

```
lib\bindbc-glfw\source\bindbc\glfw\binddynamic.d(326,24): Error: `name.ptr` cannot be used in `@safe` code, use `&name[0]` instead
lib\bindbc-glfw\source\bindbc\glfw\binddynamic.d(342,33): Error: `@safe` function `loadGLFW` cannot access `__gshared` data `glfwInit`
lib\bindbc-glfw\source\bindbc\glfw\binddynamic.d(342,20): Error: cast from `extern (C) int function() nothrow @nogc*` to `void**` not allowed in safe code
lib\bindbc-glfw\source\bindbc\glfw\binddynamic.d(343,33): Error: `@safe` function `loadGLFW` cannot access `__gshared` data `glfwTerminate`
lib\bindbc-glfw\source\bindbc\glfw\binddynamic.d(343,20): Error: cast from `extern (C) void function() nothrow @nogc*` to `void**` not allowed in safe code
lib\bindbc-glfw\source\bindbc\glfw\binddynamic.d(344,33): Error: `@safe` function `loadGLFW` cannot access `__gshared` data `glfwGetVersion`
```

Still it's a great step forward, thanks for your work~