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#![doc = include_str!("../README.md")]
#![no_std]
#![cfg_attr(feature = "polonius",
forbid(unsafe_code),
)]
pub
mod prelude {
pub use crate::{
polonius,
polonius_return,
polonius_break,
};
}
pub
trait WithLifetime<'lt, Bound = &'lt Self> {
type T;
}
pub
trait HKT
where
Self : for<'any> WithLifetime<'any>,
{}
impl<T : ?Sized> HKT for T
where
Self : for<'any> WithLifetime<'any>,
{}
pub
fn polonius<Ret : HKT, State : ?Sized, Err, F> (
state: &mut State,
scope: F,
) -> Result<
<Ret as WithLifetime<'_>>::T,
(&'_ mut State, Err),
>
where
F : FnOnce(&'_ mut State)
-> Result<
<Ret as WithLifetime<'_>>::T,
Err,
>,
{
let err = {
#[cfg(not(feature = "polonius"))]
let state = unsafe {
&mut *(state as *mut _)
};
match scope(state) {
| Ok(ret) => return Ok(ret),
| Err(err) => err,
}
};
Err((state, err))
}
#[macro_export]
macro_rules! polonius {(
$(
<
$( $($lt:lifetime),+ $(,)? )?
$( $($T:ident),+ $(,)? )?
>
)?
|$var:ident| -> $Ret:ty $body:block
) => ({
#[allow(nonstandard_style)]
struct __polonius_the_crab_Ret <$(
$($($lt ,)+)?
$($($T ,)+)?
)?> (
*mut Self,
);
impl<'polonius, $($($($lt ,)+)? $($($T ,)+)?)?>
$crate::WithLifetime<'polonius>
for
__polonius_the_crab_Ret<$(
$($($lt ,)+)?
$($($T ,)+)?
)?>
{
type T = $Ret;
}
match
$crate::polonius::<
__polonius_the_crab_Ret<$(
$($($T ,)+)?
)?>,
_,
_,
_,
>(
$var,
|mut $var: &mut _| {
$var = $var;
$crate::ඞ::core::result::Result::Err($body)
},
)
{
| $crate::ඞ::core::result::Result::Ok(ret) => return ret,
| $crate::ඞ::core::result::Result::Err((give_input_back, bail_value)) => {
$var = give_input_back;
bail_value
},
}
})}
#[macro_export]
macro_rules! polonius_return {( $e:expr $(,)? ) => (
return $crate::ඞ::core::result::Result::Ok($e)
)}
#[macro_export]
macro_rules! polonius_break {( $($e:expr $(,)?)? ) => (
return $crate::ඞ::core::result::Result::Err(($($e)?))
)}
#[doc(hidden)] pub
mod ඞ {
pub use ::core;
}
#[cfg_attr(feature = "ui-tests",
cfg_attr(all(), doc = include_str!("compile_fail_tests.md")),
)]
mod _compile_fail_tests {}