Trait pyo3::conversion::FromPyObjectBound
source · pub trait FromPyObjectBound<'a, 'py>: Sized + Sealed {
// Required method
fn from_py_object_bound(ob: Borrowed<'a, 'py, PyAny>) -> PyResult<Self>;
// Provided method
fn type_input() -> TypeInfo { ... }
}Expand description
Expected form of FromPyObject to be used in a future PyO3 release.
The difference between this and FromPyObject is that this trait takes an
additional lifetime 'a, which is the lifetime of the input Bound.
This allows implementations for &'a str and &'a [u8], which could not
be expressed by the existing FromPyObject trait once the GIL Refs API was
removed.
§Usage
Users are prevented from implementing this trait, instead they should implement
the normal FromPyObject trait. This trait has a blanket implementation
for T: FromPyObject.
The only case where this trait may have a use case to be implemented is when the
lifetime of the extracted value is tied to the lifetime 'a of the input Bound
instead of the GIL lifetime py, as is the case for the &'a str implementation.
Please contact the PyO3 maintainers if you believe you have a use case for implementing
this trait before PyO3 is ready to change the main FromPyObject trait to take an
additional lifetime.
Similarly, users should typically not call these trait methods and should instead
use this via the extract method on Bound and Py.
Required Methods§
sourcefn from_py_object_bound(ob: Borrowed<'a, 'py, PyAny>) -> PyResult<Self>
fn from_py_object_bound(ob: Borrowed<'a, 'py, PyAny>) -> PyResult<Self>
Extracts Self from the bound smart pointer obj.
Users are advised against calling this method directly: instead, use this via
[Bound<'_, PyAny>::extract] or Py::extract.
Provided Methods§
sourcefn type_input() -> TypeInfo
fn type_input() -> TypeInfo
Extracts the type hint information for this type when it appears as an argument.
For example, Vec<u32> would return Sequence[int].
The default implementation returns Any, which is correct for any type.
For most types, the return value for this method will be identical to that of IntoPy::type_output.
It may be different for some types, such as Dict, to allow duck-typing: functions return Dict but take Mapping as argument.