[−][src]Trait cpython::FromPyObject

pub trait FromPyObject<'s>: Sized {
    fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>;
}

FromPyObject is implemented by various types that can be extracted from a Python object.

Normal usage is through the PyObject::extract helper method:

let value = obj.extract::<TargetType>(py)?;

Each target type for this conversion supports a different Python objects as input. Calls with an unsupported input object will result in an exception (usually a TypeError).

This trait is also used by the py_fn! and py_class! and py_argparse! macros in order to translate from Python objects to the expected Rust parameter types. For example, the parameter x in def method(self, x: i32) will use impl FromPyObject for i32 to convert the input Python object into a Rust i32. When these macros are used with reference parameters (x: &str), the trait RefFromPyObject is used instead.

Required methods

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`

Extracts Self from the source PyObject.

Loading content...

Implementations on Foreign Types

`impl<'s, T> FromPyObject<'s> for Option<T> where T: FromPyObject<'s>,` [src]

If the python value is None, returns Option::None. Otherwise, converts the python value to T and returns Some(T).

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for bool`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

Converts a Python bool to a rust bool.

Fails with TypeError if the input is not a Python bool.

`impl<'s> FromPyObject<'s> for i8`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for u8`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for i16`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for u16`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for i32`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for u32`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for i64`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for isize`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for usize`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for u64`[src]

Converts Python integers to Rust integers.

Returns OverflowError if the input integer does not fit the Rust type; or TypeError if the input is not an integer.

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<u64>`[src]

`impl<'s> FromPyObject<'s> for f64`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for f32`[src]

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s, T> FromPyObject<'s> for Vec<T> where T: FromPyObject<'a>,` [src]

Uses the sequence protocol and converts each individual element via impl FromPyObject for T.

Note: when using --features nightly, a specialization of this impl may use the buffer protocol to perform a more efficient bulk copy.

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for Cow<'s, str>`[src]

Allows extracting strings from Python objects. Accepts Python str and unicode objects. In Python 2.7, str is expected to be UTF-8 encoded.

Returns a UnicodeDecodeError if the input is not valid unicode (containing unpaired surrogates, or a Python 2.7 byte string that is not valid UTF-8).

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for String`[src]

Allows extracting strings from Python objects. Accepts Python str and unicode objects. In Python 2.7, str is expected to be UTF-8 encoded.

Returns a UnicodeDecodeError if the input is not valid unicode (containing unpaired surrogates, or a Python 2.7 byte string that is not valid UTF-8).

`fn extract(py: Python, obj: &'s PyObject) -> PyResult<Self>`[src]

`impl<'s> FromPyObject<'s> for Cow<'s, [u8]>`[src]

For Python bytes, returns a reference to the existing immutable string data. If the Python object is a single-dimensional buffer of format c or B (C: char or unsigned char), returns an owned copy of the data in the buffer. Otherwise, uses the sequence protocol and converts each individual element via impl FromPyObject for u8.