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Diffstat (limited to 'vendor/rowan/src/cow_mut.rs')
-rw-r--r-- | vendor/rowan/src/cow_mut.rs | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/vendor/rowan/src/cow_mut.rs b/vendor/rowan/src/cow_mut.rs new file mode 100644 index 000000000..c50e25b70 --- /dev/null +++ b/vendor/rowan/src/cow_mut.rs @@ -0,0 +1,30 @@ +#[derive(Debug)] +pub(crate) enum CowMut<'a, T> { + Owned(T), + Borrowed(&'a mut T), +} + +impl<T> std::ops::Deref for CowMut<'_, T> { + type Target = T; + fn deref(&self) -> &T { + match self { + CowMut::Owned(it) => it, + CowMut::Borrowed(it) => *it, + } + } +} + +impl<T> std::ops::DerefMut for CowMut<'_, T> { + fn deref_mut(&mut self) -> &mut T { + match self { + CowMut::Owned(it) => it, + CowMut::Borrowed(it) => *it, + } + } +} + +impl<T: Default> Default for CowMut<'_, T> { + fn default() -> Self { + CowMut::Owned(T::default()) + } +} |