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author | FintanH | 2019-08-12 22:34:21 +0100 |
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committer | FintanH | 2019-08-12 22:34:21 +0100 |
commit | 4a86274878d5ab0ef4f9d8597606226adfd048de (patch) | |
tree | 68153eb0e4283740f49042e059402da6eaaf551e /dhall_syntax/src/core/map.rs | |
parent | 405bc3d80c0e169ea74dd12422b9504b7383dab3 (diff) | |
parent | 7d17d39005531cb77d8eaf32ed7de8938c66f874 (diff) |
Merge remote-tracking branch 'origin/master' into fintan/canonicalize
Diffstat (limited to 'dhall_syntax/src/core/map.rs')
-rw-r--r-- | dhall_syntax/src/core/map.rs | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/dhall_syntax/src/core/map.rs b/dhall_syntax/src/core/map.rs index 63f19cd..6a0ebda 100644 --- a/dhall_syntax/src/core/map.rs +++ b/dhall_syntax/src/core/map.rs @@ -1,5 +1,6 @@ /// A sorted map that allows multiple values for each key. pub use dup_tree_map::DupTreeMap; +pub use dup_tree_set::DupTreeSet; mod one_or_more { use either::Either; @@ -232,3 +233,97 @@ mod dup_tree_map { // unsafe impl<K, V> iter::TrustedLen for IntoIter<K, V> {} } + +mod dup_tree_set { + use super::DupTreeMap; + use std::iter; + + #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)] + pub struct DupTreeSet<K> { + map: DupTreeMap<K, ()>, + } + + pub type Iter<'a, K> = iter::Map< + super::dup_tree_map::Iter<'a, K, ()>, + for<'b> fn((&'b K, &'b ())) -> &'b K, + >; + pub type IntoIter<K> = + iter::Map<super::dup_tree_map::IntoIter<K, ()>, fn((K, ())) -> K>; + + impl<K> DupTreeSet<K> { + pub fn new() -> Self + where + K: Ord, + { + DupTreeSet { + map: DupTreeMap::new(), + } + } + + pub fn len(&self) -> usize { + self.map.len() + } + pub fn is_empty(&self) -> bool { + self.map.is_empty() + } + + pub fn iter(&self) -> Iter<'_, K> + where + K: Ord, + { + fn foo<'a, K>((k, ()): (&'a K, &'a ())) -> &'a K { + k + } + self.map.iter().map(foo) + } + } + + impl<K> Default for DupTreeSet<K> + where + K: Ord, + { + fn default() -> Self { + Self::new() + } + } + + impl<K> IntoIterator for DupTreeSet<K> + where + K: Ord + Clone, + { + type Item = K; + type IntoIter = IntoIter<K>; + + fn into_iter(self) -> Self::IntoIter { + fn foo<K>((k, ()): (K, ())) -> K { + k + } + self.map.into_iter().map(foo) + } + } + + impl<'a, K> IntoIterator for &'a DupTreeSet<K> + where + K: Ord, + { + type Item = &'a K; + type IntoIter = Iter<'a, K>; + + fn into_iter(self) -> Self::IntoIter { + self.iter() + } + } + + impl<K> iter::FromIterator<K> for DupTreeSet<K> + where + K: Ord, + { + fn from_iter<T>(iter: T) -> Self + where + T: IntoIterator<Item = K>, + { + let map = iter.into_iter().map(|k| (k, ())).collect(); + DupTreeSet { map } + } + } +} |