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Diffstat (limited to 'compiler/rustc_data_structures/src')
| -rw-r--r-- | compiler/rustc_data_structures/src/unord.rs | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/compiler/rustc_data_structures/src/unord.rs b/compiler/rustc_data_structures/src/unord.rs index 34895d3efe6..90a77e1e580 100644 --- a/compiler/rustc_data_structures/src/unord.rs +++ b/compiler/rustc_data_structures/src/unord.rs @@ -259,6 +259,12 @@ impl<V: Eq + Hash> UnordSet<V> { self.inner.is_empty() } + /// If the set has only one element, returns it, otherwise returns `None`. + #[inline] + pub fn get_only(&self) -> Option<&V> { + if self.inner.len() == 1 { self.inner.iter().next() } else { None } + } + #[inline] pub fn insert(&mut self, v: V) -> bool { self.inner.insert(v) |