Add ResultNoneExt

3 files changed, 71 insertions, 4 deletions

diff --git a/src/exun.rs b/src/exun.rs
index 87e8610..0dcd936 100644
--- a/src/exun.rs
+++ b/src/exun.rs
@@ -3,7 +3,6 @@ use core::fmt::{self, Debug, Display};
 #[cfg(feature = "std")]
 use std::error::Error;
 
-#[cfg(feature = "alloc")]
 use crate::{RawUnexpected, UnexpectedError};
 
 pub use Exun::{Expected, Unexpected};
@@ -56,14 +55,12 @@ impl<E: Error, U> From<E> for Exun<E, U> {
 	}
 }
 
-#[cfg(feature = "alloc")]
 impl<E> From<RawUnexpected> for Exun<E, RawUnexpected> {
 	fn from(ue: RawUnexpected) -> Self {
 		Unexpected(ue)
 	}
 }
 
-#[cfg(feature = "alloc")]
 impl<E> From<RawUnexpected> for Exun<E, UnexpectedError> {
 	fn from(ue: RawUnexpected) -> Self {
 		Unexpected(ue.into())
diff --git a/src/lib.rs b/src/lib.rs
index 742cc60..8412e2a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -156,7 +156,7 @@ pub use result::ResultErrorExt;
 pub use result::ResultMsgExt;
 
 pub use crate::exun::Exun;
-pub use result::ResultExunExt;
+pub use result::{ResultExunExt, ResultNoneExt};
 pub use unexpected::{RawUnexpected, UnexpectedError};
 pub use Exun::{Expected, Unexpected};
 
diff --git a/src/result.rs b/src/result.rs
index 0bef098..f31df2b 100644
--- a/src/result.rs
+++ b/src/result.rs
@@ -133,6 +133,76 @@ impl<T, E: Errorable + 'static> ResultMsgExt<T> for Result<T, E> {
 	}
 }
 
+/// Provides [`Result::unexpect_none`] and [`Option::unexpect_none`]
+///
+/// [`Result::unexpect_none`]: `ResultNoneExt::unexpect_none`
+/// [`Option::unexpect_none`]: `ResultNoneExt::unexpect_none`
+pub trait ResultNoneExt<T>: Sealed {
+	/// Converts [`Result<T, E>`] or [`Option<T>`] to
+	/// [`Result<T, RawUnexpected>`].
+	///
+	/// # Examples
+	///
+	/// ```
+	/// use exun::*;
+	/// use core::fmt::Error;
+	///
+	/// let res: Result<i32, Error> = Err(Error);
+	/// let res: Result<i32, RawUnexpected> = res.unexpect_none();
+	/// ```
+	///
+	/// Use with the try operator
+	///
+	/// ```
+	/// use exun::*;
+	/// use core::fmt::Error;
+	///
+	/// fn foo() -> Result<i32, UnexpectedError> {
+	///     let res: Result<i32, Error> = Err(Error);
+	///     Ok(res.unexpect_none()?)
+	/// }
+	/// ```
+	///
+	/// Use with the try operator and [`Exun`]
+	///
+	/// ```
+	/// use exun::*;
+	/// use core::fmt::Error;
+	///
+	/// fn foo() -> Result<i32, Exun<(), UnexpectedError>> {
+	///     let res: Result<i32, Error> = Err(Error);
+	///     Ok(res.unexpect_none()?)
+	/// }
+	/// ```
+	///
+	/// Use with [`Option`]
+	///
+	/// ```
+	/// use exun::*;
+	///
+	/// fn foo() -> Result<i32, UnexpectedError> {
+	///     let option: Option<i32> = None;
+	///     Ok(option.unexpect_none()?)
+	/// }
+	/// ```
+	///
+	/// [`Exun`]: `crate::Exun`
+	#[allow(clippy::missing_errors_doc)]
+	fn unexpect_none(self) -> Result<T, RawUnexpected>;
+}
+
+impl<T, E> ResultNoneExt<T> for Result<T, E> {
+	fn unexpect_none(self) -> Result<T, RawUnexpected> {
+		self.map_or_else(|_| Err(RawUnexpected::none()), |val| Ok(val))
+	}
+}
+
+impl<T> ResultNoneExt<T> for Option<T> {
+	fn unexpect_none(self) -> Result<T, RawUnexpected> {
+		self.ok_or_else(RawUnexpected::none)
+	}
+}
+
 pub trait ResultExunExt<T, E, U>: Sealed {
 	/// Converts [`Result<T, Exun<E, U>>`] to [`Option<E>`].
 	///