pyo3/src/internal_tricks.rs
Georg Brandl 79d9741906 Add PyList::slice and fix index types of PyTuple::slice, PyList::insert and PyList::set_item.
NB: the behavior on out-of-range indices hasn't changed;
it was merely wrongly documented before.

See #1667
2021-08-17 09:45:06 +02:00

61 lines
1.8 KiB
Rust

use crate::ffi::{Py_ssize_t, PY_SSIZE_T_MAX};
use std::ffi::{CStr, CString};
use std::marker::PhantomData;
use std::rc::Rc;
/// A marker type that makes the type !Send.
/// Temporal hack until https://github.com/rust-lang/rust/issues/13231 is resolved.
pub(crate) type Unsendable = PhantomData<Rc<()>>;
pub struct PrivateMarker;
macro_rules! private_decl {
() => {
/// This trait is private to implement; this method exists to make it
/// impossible to implement outside the crate.
fn __private__(&self) -> crate::internal_tricks::PrivateMarker;
};
}
macro_rules! private_impl {
() => {
#[doc(hidden)]
fn __private__(&self) -> crate::internal_tricks::PrivateMarker {
crate::internal_tricks::PrivateMarker
}
};
}
macro_rules! pyo3_exception {
($doc: expr, $name: ident, $base: ty) => {
#[doc = $doc]
#[repr(transparent)]
#[allow(non_camel_case_types)]
pub struct $name($crate::PyAny);
$crate::impl_exception_boilerplate!($name);
$crate::create_exception_type_object!(pyo3_runtime, $name, $base);
};
}
#[derive(Debug)]
pub(crate) struct NulByteInString(pub(crate) &'static str);
pub(crate) fn extract_cstr_or_leak_cstring(
src: &'static str,
err_msg: &'static str,
) -> Result<&'static CStr, NulByteInString> {
CStr::from_bytes_with_nul(src.as_bytes())
.or_else(|_| {
CString::new(src.as_bytes()).map(|c_string| &*Box::leak(c_string.into_boxed_c_str()))
})
.map_err(|_| NulByteInString(err_msg))
}
/// Convert an usize index into a Py_ssize_t index, clamping overflow to
/// PY_SSIZE_T_MAX.
pub(crate) fn get_ssize_index(index: usize) -> Py_ssize_t {
index.min(PY_SSIZE_T_MAX as usize) as Py_ssize_t
}