lender 0.6.2

A lending-iterator trait based on higher-rank trait bounds, with full std::iter::Iterator functionality
Documentation 
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use crate::TryShunt;

mod chain;
mod chunk;
mod chunky;
mod cloned;
mod convert;
mod copied;
mod cycle;
mod enumerate;
mod filter;
mod filter_map;
mod flatten;
mod fuse;
mod inspect;
mod intersperse;
mod into_fallible;
mod iter;
mod map;
mod map_err;
mod map_into_iter;
mod map_while;
mod mutate;
pub(crate) mod non_fallible_adapter;
mod owned;
mod peekable;
mod rev;
mod scan;
mod skip;
mod skip_while;
mod step_by;
mod take;
mod take_while;
mod zip;

pub use convert::Convert;
pub use flatten::{FlatMap as FallibleFlatMap, Flatten as FallibleFlatten};
pub use intersperse::{
    Intersperse as FallibleIntersperse, IntersperseWith as FallibleIntersperseWith,
};
pub use into_fallible::IntoFallible;
pub use map_err::MapErr;
pub(crate) use non_fallible_adapter::NonFallibleAdapter;
pub use peekable::Peekable as FalliblePeekable;

pub type FallibleTryShuntAdapter<'a, 'b, 'c, 'd, L> =
    TryShunt<'a, &'b mut NonFallibleAdapter<'c, &'d mut L>>;

use crate::try_trait_v2::Try;
use core::ops::ControlFlow;

/// Converts a `Result<R, E>` from a fallible fold closure
/// into a [`ControlFlow`] for delegation to an inner
/// lender's `try_fold`/`try_rfold`.
///
/// Used by [`Convert`] and [`MapErr`] to bridge between
/// the user's fold closure (which returns `Result<R, E>`)
/// and the inner lender's fold (which expects a
/// [`ControlFlow`]). `Ok(r)` is branched via
/// [`Try::branch`] to propagate short-circuits, while
/// `Err(e)` becomes `Break(Err(e))`.
#[inline]
fn try_fold_with<B, R, E>(result: Result<R, E>) -> ControlFlow<Result<R, E>, B>
where
    R: Try<Output = B>,
{
    match result {
        Ok(r) => match r.branch() {
            ControlFlow::Continue(b) => ControlFlow::Continue(b),
            ControlFlow::Break(residual) => ControlFlow::Break(Ok(R::from_residual(residual))),
        },
        Err(e) => ControlFlow::Break(Err(e)),
    }
}