what happens if the struct is not ref

K

Kai•8/4/23, 8:12 PM

Idk if this is more ergonomic then RefMutRefInt but, maybe

MMaxine what happens if the struct is not ref

P

Perksey•8/4/23, 8:12 PM

ByReference<T> is a ref struct because... it's a ref

K

Kai•8/4/23, 8:12 PM

ByReference<T> was a ref struct before it was cool

P

Perksey•8/4/23, 8:12 PM

so it won't be allowed in anything but a ref struct

M

MaxineOP•8/4/23, 8:12 PM

ohhhh right i didn't even see that

KKai ```cs public ref struct PtrType<T> { // inner magic to store the arbitrary p...

K

Kai•8/4/23, 8:13 PM

@Perksey thoughts?

P

Perksey•8/4/23, 8:13 PM

there's not enough there for me to have any thoughts really, i don't know how that'd actually work

P

Perksey•8/4/23, 8:14 PM

for reference the desired user experience is just taking something you can take a ref to and doing

.AsPtr

.AsPtr

.AsPtr

.AsPtr or

.AsMut

.AsMut

.AsMut

.AsMut

M

MaxineOP•8/4/23, 8:14 PM

where does the ref go

M

MaxineOP•8/4/23, 8:14 PM

wait i kinda see what kai is cooking here

P

Perksey•8/4/23, 8:14 PM

e.g.:

    // -------------------vvvvvvvv-- returns a ref struct
    if (glfwGetError(error.AsPtr2D()) == 0 || error == nullptr)
    {
        throw new Exception("failed to create window and failed to get error");
    }

    // -------------------vvvvvvvv-- returns a ref struct
    if (glfwGetError(error.AsPtr2D()) == 0 || error == nullptr)
    {
        throw new Exception("failed to create window and failed to get error");
    }

    // -------------------vvvvvvvv-- returns a ref struct
    if (glfwGetError(error.AsPtr2D()) == 0 || error == nullptr)
    {
        throw new Exception("failed to create window and failed to get error");
    }

    // -------------------vvvvvvvv-- returns a ref struct
    if (glfwGetError(error.AsPtr2D()) == 0 || error == nullptr)
    {
        throw new Exception("failed to create window and failed to get error");
    }

K

Kai•8/4/23, 8:15 PM

uh I thought that'd be enough. PtrType can then have the "normal"

private readonly ref byte InteriorRef;

private readonly ref byte InteriorRef;

private readonly ref byte InteriorRef;

private readonly ref byte InteriorRef; and then that works?
We calculate the inner in

Inner

Inner

Inner

Inner (or whatever it's called) and return another

PtrType<T>

PtrType<T>

PtrType<T>

PtrType<T>.
All the other methods work the same as Any2D but with generics

A

Aqua•8/4/23, 8:15 PM

maybe i have come in at the wrong time - but has the prospect of having 2 overloads, a safe and unsafe, been ruled out?
on a personal level, this is what i would prefer to see. it's how i tend to structure my apis as well - if you take a look at pie you'll see that pretty much everything that takes an array also has a pointer overload
but it's one or the other, no combinations

PPerksey e.g.: ```cs // -------------------vvvvvvvv-- returns a ref struct if (gl...

M

MaxineOP•8/4/23, 8:15 PM

that should still work with this design

PPerksey e.g.: ```cs // -------------------vvvvvvvv-- returns a ref struct if (gl...

K

Kai•8/4/23, 8:15 PM

what is error here?

SomeT**

SomeT**

SomeT**

SomeT**?

AAqua maybe i have come in at the wrong time - but has the prospect of having 2 overlo...

M

MaxineOP•8/4/23, 8:16 PM

if you want to do things unsafely there could probably be an implicit cast from pointer to Ptr<T> if that's allowed in c#

P

Perksey•8/4/23, 8:16 PM

error is

ConstPtr<sbyte>

ConstPtr<sbyte>

ConstPtr<sbyte>

ConstPtr<sbyte> in this instance

AAqua maybe i have come in at the wrong time - but has the prospect of having 2 overlo...

K

Kai•8/4/23, 8:16 PM

unsafe overloads will stay, I'm very confident to say that

P

Perksey•8/4/23, 8:16 PM

NO OVERLOADS

K

Kai•8/4/23, 8:16 PM

unsafe ways to call the function

K

Kai•8/4/23, 8:16 PM

whatever

M

MaxineOP•8/4/23, 8:16 PM

a cast that doesn't change the underlying memory of the value is free

P

Perksey•8/4/23, 8:16 PM

the JIT is smart enough that if for every

Ptr

Ptr

Ptr

Ptr you implicitly cast from a

something*

something*

something*

something*, it will be equivalent to fully unsafe

PPerksey error is `ConstPtr<sbyte>` in this instance

K

Kai•8/4/23, 8:17 PM

? So what does AsPtr2D() return? that makes no sense to me

P

Perksey•8/4/23, 8:17 PM

ConstPtr<sbyte>

ConstPtr<sbyte>

ConstPtr<sbyte>

ConstPtr<sbyte> incorrectly returns

ConstPtr2D<sbyte>

ConstPtr2D<sbyte>

ConstPtr2D<sbyte>

ConstPtr2D<sbyte> atm

KKai ? So what does AsPtr2D() return? that makes no sense to me

M

MaxineOP•8/4/23, 8:17 PM

sbyte* to sbyte**, i presume

P

Perksey•8/4/23, 8:17 PM

i.e. it converts a

ref this ConstPtr<sbyte>

ref this ConstPtr<sbyte>

ref this ConstPtr<sbyte>

ref this ConstPtr<sbyte> to a

ConstPtr2D<sbyte>

ConstPtr2D<sbyte>

ConstPtr2D<sbyte>

ConstPtr2D<sbyte>

P

Perksey•8/4/23, 8:17 PM

(or in IL terms,

ldarg.0

ldarg.0

ldarg.0

ldarg.0

ret

ret

ret

ret)

K

Kai•8/4/23, 8:18 PM

ah

K

Kai•8/4/23, 8:18 PM

ref

K

Kai•8/4/23, 8:18 PM

I see where the extra comes from now

K

Kai•8/4/23, 8:18 PM

implicit ref

P

Perksey•8/4/23, 8:18 PM

lmao

P

Perksey•8/4/23, 8:18 PM

i'm sorry I just found that hilarious

P

Perksey•8/4/23, 8:18 PM

PPerksey NO OVERLOADS

A

Aqua•8/4/23, 8:18 PM

hmm that's where i disagree
one of the big benefits of C# is that it has overloads
sure you can have too many of them
but if you only have a few they can work very well
a pointer overload and an array overload
maybe a span
i just feel like this

Ptr<T>

Ptr<T>

stuff may be a bit hard to understand, certainly i'm looking at this and wondering what exactly this is supposed to mean
i feel like for most users, they will only ever want safe overloads that take an array/whatever else, instead of a

Ptr<T>

Ptr<T>

struct that may leave (especially to beginners) some users scratching their heads
and for those that want pointer overloads, they are available as well

K

Kai•8/4/23, 8:18 PM

yeah so that way around I see no problem with my design? It would work fine, the same way it works now. Use some IL magic to load the arg ptr and then store it into the outer PtrType ref struct

K

Kai•8/4/23, 8:19 PM

(but also do generic magic so the compiler knows what indirection level we are at now, but this isn't a runtime thing)

K

Kai•8/4/23, 8:19 PM

(unfortunately the JIT won't see it that way and produce many re-compilations of the same IL but that's not on me)

K

Kai•8/4/23, 8:19 PM

(and also also the case with The RefMutRef design)

P

Perksey•8/4/23, 8:19 PM

can you define an E2E of how it'll work with a dummy glfwGetError signature, sorry just being stupid and can't quite visualise it

K

Kai•8/4/23, 8:19 PM

eeeh

K

Kai•8/4/23, 8:20 PM

can you give me the E2E I'm supposed to translate? I don't know what it looks like right now

P

Perksey•8/4/23, 8:21 PM

what would

int glfwGetError(const char**)

int glfwGetError(const char**)

int glfwGetError(const char**)

int glfwGetError(const char**) (i.e.

sbyte**

sbyte**

sbyte**

sbyte**) look like, how would the user use it, and what does the AsPtr2D (or whatever) have to do to make it work

M

MaxineOP•8/4/23, 8:22 PM

PtrType<sbyte> a = ???;

PtrType<Ptr<sbyte>> b = a.PtrTo();

glfwGetError(b);

PtrType<sbyte> a = ???;

PtrType<Ptr<sbyte>> b = a.PtrTo();

glfwGetError(b);

PtrType<sbyte> a = ???;

PtrType<Ptr<sbyte>> b = a.PtrTo();

glfwGetError(b);

PtrType<sbyte> a = ???;

PtrType<Ptr<sbyte>> b = a.PtrTo();

glfwGetError(b);

K

Kai•8/4/23, 8:22 PM

int glfwError(ConstPtrType<Ptr<sbyte>>)

int glfwError(ConstPtrType<Ptr<sbyte>>)

int glfwError(ConstPtrType<Ptr<sbyte>>)

int glfwError(ConstPtrType<Ptr<sbyte>>)

MMaxine ```cs PtrType<sbyte> a = ???; PtrType<Ptr<sbyte>> b = a.PtrTo(); glfwGetError(...

K

Kai•8/4/23, 8:22 PM

and that

K

Kai•8/4/23, 8:22 PM

just ConstPtrType on the outside I think

M

MaxineOP•8/4/23, 8:23 PM

i foind a problem

P

Perksey•8/4/23, 8:23 PM

and presumably if I did

PtrType<sbyte> a = nullptr;
PtrType<Ptr<sbyte> b = a.PtrTo();
glfwGetError(b);
Debug.Assert(a != nullptr);

PtrType<sbyte> a = nullptr;
PtrType<Ptr<sbyte> b = a.PtrTo();
glfwGetError(b);
Debug.Assert(a != nullptr);

PtrType<sbyte> a = nullptr;
PtrType<Ptr<sbyte> b = a.PtrTo();
glfwGetError(b);
Debug.Assert(a != nullptr);

PtrType<sbyte> a = nullptr;
PtrType<Ptr<sbyte> b = a.PtrTo();
glfwGetError(b);
Debug.Assert(a != nullptr);

it'd pass?

what happens if the struct is not ref

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