Skip to content

Low-level Interfaces

Within optype.numpy there are several Can* (single-method) and Has* (single-attribute) protocols, related to the __array_*__ dunders of the NumPy Python API. These typing protocols are, just like the optype.Can* and optype.Has* ones, runtime-checkable and extensible (i.e. not @final).

Tip

All type parameters of these protocols can be omitted, which is equivalent to passing its upper type bound.

Protocol type signature Implements NumPy docs 
class CanArray[
    ND: tuple[int, ...] = ...,
    ST: np.generic = ...,
]: ...

def __array__[RT = ST](
    _,
    dtype: DType[RT] | None = ...,
) -> Array[ND, RT]
User Guide: Interoperability with NumPy 
class CanArrayUFunc[
    U: UFunc = ...,
    R: object = ...,
]: ...

def __array_ufunc__(
    _,
    ufunc: U,
    method: LiteralString,
    *args: object,
    **kwargs: object,
) -> R: ...
NEP 13 
class CanArrayFunction[
    F: CanCall[..., object] = ...,
    R = object,
]: ...

def __array_function__(
    _,
    func: F,
    types: CanIterSelf[type[CanArrayFunction]],
    args: tuple[object, ...],
    kwargs: Mapping[str, object],
) -> R: ...
NEP 18 
class CanArrayFinalize[
    T: object = ...,
]: ...

def __array_finalize__(_, obj: T): ...
User Guide: Subclassing ndarray 
class CanArrayWrap: ...

def __array_wrap__[ND, ST](
    _,
    array: Array[ND, ST],
    context: (...) | None = ...,
    return_scalar: bool = ...,
) -> Self | Array[ND, ST]
API: Standard array subclasses 
class HasArrayInterface[
    V: Mapping[str, object] = ...,
]: ...

__array_interface__: V
API: The array interface protocol 
class HasArrayPriority: ...

__array_priority__: float
API: Standard array subclasses 
class HasDType[
    DT: DType = ...,
]: ...

dtype: DT
API: Specifying and constructing data types