add mut version

.gitignore

@@ -0,0 +1,2 @@
+target/
+

Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "maybe_owned"
+version = "0.1.0"

src/lib.rs

@@ -1,22 +1,110 @@
+use std::{
+    borrow::Cow,
+    ops::{Deref, DerefMut},
+};
+
+#[derive(Clone, Copy, Debug)]
 pub enum MaybeOwned<'a, T: 'a> {
     Owned(T),
     Borrowed(&'a T),
 }
 
+impl<'a, T> Deref for MaybeOwned<'a, T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        match self {
+            MaybeOwned::Owned(v) => v,
+            MaybeOwned::Borrowed(v) => v,
+        }
+    }
+}
+
 impl<'a, T: 'a> From<T> for MaybeOwned<'a, T> {
     fn from(value: T) -> Self {
         Self::Owned(value)
     }
 }
 
+impl<'a, T: 'a> From<MaybeOwnedMut<'a, T>> for MaybeOwned<'a, T> {
+    fn from(value: MaybeOwnedMut<'a, T>) -> Self {
+        match value {
+            MaybeOwnedMut::Owned(v) => MaybeOwned::Owned(v),
+            MaybeOwnedMut::Borrowed(v) => MaybeOwned::Borrowed(v),
+        }
+    }
+}
+
 impl<'a, T: 'a> From<&'a T> for MaybeOwned<'a, T> {
     fn from(value: &'a T) -> Self {
         Self::Borrowed(value)
     }
 }
 
+impl<'a, T: 'a + Clone> From<Cow<'a, T>> for MaybeOwned<'a, T> {
+    fn from(value: Cow<'a, T>) -> Self {
+        match value {
+            Cow::Owned(v) => MaybeOwned::Owned(v),
+            Cow::Borrowed(v) => MaybeOwned::Borrowed(v),
+        }
+    }
+}
+
 impl<'a, T: 'a + Default> Default for MaybeOwned<'a, T> {
     fn default() -> Self {
         MaybeOwned::Owned(T::default())
     }
 }
+
+#[derive(Debug)]
+pub enum MaybeOwnedMut<'a, T: 'a> {
+    Owned(T),
+    Borrowed(&'a mut T),
+}
+
+impl<'a, T: 'a + Clone> Clone for MaybeOwnedMut<'a, T> {
+    fn clone(&self) -> Self {
+        match self {
+            Self::Owned(v) => Self::Owned(v.clone()),
+            Self::Borrowed(v) => Self::Owned((*v).to_owned()),
+        }
+    }
+}
+
+impl<'a, T> Deref for MaybeOwnedMut<'a, T> {
+    type Target = T;
+
+    fn deref(&self) -> &Self::Target {
+        match self {
+            MaybeOwnedMut::Owned(v) => v,
+            MaybeOwnedMut::Borrowed(v) => *v,
+        }
+    }
+}
+
+impl<'a, T> DerefMut for MaybeOwnedMut<'a, T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        match self {
+            MaybeOwnedMut::Owned(v) => v,
+            MaybeOwnedMut::Borrowed(v) => *v,
+        }
+    }
+}
+
+impl<'a, T: 'a> From<T> for MaybeOwnedMut<'a, T> {
+    fn from(value: T) -> Self {
+        Self::Owned(value)
+    }
+}
+
+impl<'a, T: 'a> From<&'a mut T> for MaybeOwnedMut<'a, T> {
+    fn from(value: &'a mut T) -> Self {
+        Self::Borrowed(value)
+    }
+}
+
+impl<'a, T: 'a + Default> Default for MaybeOwnedMut<'a, T> {
+    fn default() -> Self {
+        MaybeOwnedMut::Owned(T::default())
+    }
+}