Enum ExternalQueue 

#[non_exhaustive]
pub enum ExternalQueue<'a> {
    WgpuEncoder(&'a mut CommandEncoder),
    OpenClQueue(&'a ClQueueRef),
    CudaStream(&'a CudaStreamRef),
    MetalCommandBuffer(&'a MtlCommandBufferRef),
    Cpu,
    _Phantom(PhantomData<&'a ()>),
}

Borrowed handle into an external command queue. The 'a lifetime ties the queue to the caller’s scope so the borrow-checker prevents reentrant use across the call it is lent to.

The payloads are the typed handle newtypes re-exported at the crate root — MtlCommandBufferRef and, under the matching feature, ClQueueRef / CudaStreamRef — rather than bare *mut c_voids. Construction of each newtype happens once at the call-site boundary via its try_from_raw(unsafe { ... }); pattern-match arms inside backends are safe code.

_Phantom variant exists so 'a remains load-bearing under --no-default-features (where every other typed variant is cfg’d out).

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

WgpuEncoder(&'a mut CommandEncoder)

Available on crate feature wgpu only.

OpenClQueue(&'a ClQueueRef)

Available on crate feature opencl only.

CudaStream(&'a CudaStreamRef)

Available on crate feature cuda only.

MetalCommandBuffer(&'a MtlCommandBufferRef)

Cpu

_Phantom(PhantomData<&'a ()>)

Implementations

impl ExternalQueue<'_>

pub fn backend(&self) -> BackendKind

Trait Implementations

impl Debug for ExternalQueue<'_>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.