Struct PyUntypedBufferView 

pub struct PyUntypedBufferView<Flags: PyBufferFlagsType = PyBufferFlags> { /* private fields */ }

Stack-allocated untyped buffer view.

Unlike PyUntypedBuffer which heap-allocates, this places the Py_buffer on the stack. The scoped closure API ensures the buffer cannot be moved.

Use with_flags() with a PyBufferFlags value to acquire a view. The available accessors depend on the flags used.

Implementations

impl<Flags: PyBufferFlagsType> PyUntypedBufferView<Flags>

pub fn buf_ptr(&self) -> *mut c_void

Gets the pointer to the start of the buffer memory.

pub fn obj<'py>(&self, py: Python<'py>) -> Option<&Bound<'py, PyAny>>

Returns the Python object that owns the buffer data.

pub fn readonly(&self) -> bool

Gets whether the underlying buffer is read-only.

pub fn item_size(&self) -> usize

Gets the size of a single element, in bytes.

pub fn item_count(&self) -> usize

Gets the total number of items.

pub fn len_bytes(&self) -> usize

item_size() * item_count(). For contiguous arrays, this is the length of the underlying memory block.

pub fn dimensions(&self) -> usize

Gets the number of dimensions.

May be 0 to indicate a single scalar value.

pub fn suboffsets(&self) -> Option<&[isize]>

Returns the suboffsets array.

May return None even with PyBUF_INDIRECT if the exporter sets suboffsets to NULL.

pub fn is_c_contiguous(&self) -> bool

Gets whether the buffer is contiguous in C-style order.

pub fn is_fortran_contiguous(&self) -> bool

Gets whether the buffer is contiguous in Fortran-style order.

impl<const SHAPE: bool, const STRIDE: bool, const WRITABLE: bool, const CONTIGUITY: u8> PyUntypedBufferView<PyBufferFlags<true, SHAPE, STRIDE, WRITABLE, CONTIGUITY>>

pub fn format(&self) -> &CStr

A struct module style string describing the contents of a single item.

pub fn as_typed<T: Element>( &self, ) -> PyResult<&PyBufferView<T, PyBufferFlags<true, SHAPE, STRIDE, WRITABLE, CONTIGUITY>>>

Attempt to interpret this untyped view as containing elements of type T.

impl<const FORMAT: bool, const STRIDE: bool, const WRITABLE: bool, const CONTIGUITY: u8> PyUntypedBufferView<PyBufferFlags<FORMAT, true, STRIDE, WRITABLE, CONTIGUITY>>

pub fn shape(&self) -> &[usize]

Returns the shape array. shape[i] is the length of dimension i.

Despite Python using an array of signed integers, the values are guaranteed to be non-negative. However, dimensions of length 0 are possible and might need special attention.

impl<const FORMAT: bool, const SHAPE: bool, const WRITABLE: bool, const CONTIGUITY: u8> PyUntypedBufferView<PyBufferFlags<FORMAT, SHAPE, true, WRITABLE, CONTIGUITY>>

pub fn strides(&self) -> &[isize]

Returns the strides array.

Stride values can be any integer. For regular arrays, strides are usually positive, but a consumer MUST be able to handle the case strides[n] <= 0.

impl<const WRITABLE: bool> PyUntypedBufferView<PyBufferFlags<false, false, false, WRITABLE, CONTIGUITY_UNDEFINED>>

pub fn format(&self) -> &CStr

Returns the format string for a simple byte buffer, which is always "B".

impl PyUntypedBufferView

pub fn with_flags<const FORMAT: bool, const SHAPE: bool, const STRIDE: bool, const WRITABLE: bool, const CONTIGUITY: u8, R>( obj: &Bound<'_, PyAny>, flags: PyBufferFlags<FORMAT, SHAPE, STRIDE, WRITABLE, CONTIGUITY>, f: impl FnOnce(&PyUntypedBufferView<PyBufferFlags<FORMAT, SHAPE, STRIDE, WRITABLE, CONTIGUITY>>) -> R, ) -> PyResult<R>

Acquire a buffer view with the given flags, pass it to f, then release the buffer.

Use PyBufferFlags::simple() or one of the compound-request constructors such as PyBufferFlags::full_ro() to acquire a view.

Trait Implementations

impl<Flags: PyBufferFlagsType> Debug for PyUntypedBufferView<Flags>

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

Formats the value using the given formatter.

impl<Flags: PyBufferFlagsType> Drop for PyUntypedBufferView<Flags>

fn drop(&mut self)

Executes the destructor for this type.