1 files changed, 68 insertions, 0 deletions
diff --git a/oryxc/src/intern.rs b/oryxc/src/intern.rs
new file mode 100644
index 0000000..3ab91cf
--- /dev/null
+++ b/oryxc/src/intern.rs
@@ -0,0 +1,68 @@
+use std::hash;
+
+use dashmap;
+use icu::normalizer;
+
+#[repr(transparent)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
+pub struct Key(u32);
+
+pub struct Interner<'a> {
+	map:   dashmap::DashMap<UniStr<'a>, Key>,
+	store: Vec<&'a str>,
+}
+
+#[derive(Eq)]
+pub struct UniStr<'a>(pub &'a str);
+
+impl hash::Hash for UniStr<'_> {
+	fn hash<H: hash::Hasher>(&self, state: &mut H) {
+		if self.0.is_ascii() {
+            self.0.chars().for_each(|c| c.hash(state));
+		} else {
+			let nfkd = normalizer::DecomposingNormalizer::new_nfkd();
+			nfkd.normalize_iter(self.0.chars()).for_each(|c| c.hash(state));
+		}
+	}
+}
+
+impl PartialEq for UniStr<'_> {
+	fn eq(&self, other: &Self) -> bool {
+		let nfkd = normalizer::DecomposingNormalizer::new_nfkd();
+		return match (self.0.is_ascii(), other.0.is_ascii()) {
+			(true, true) => self.0 == other.0,
+			(true, false) => {
+				self.0.chars().eq(nfkd.normalize_iter(other.0.chars()))
+			},
+			(false, true) => {
+				other.0.chars().eq(nfkd.normalize_iter(self.0.chars()))
+			},
+			(false, false) => nfkd
+				.normalize_iter(self.0.chars())
+				.eq(nfkd.normalize_iter(other.0.chars())),
+		};
+	}
+}
+
+impl<'a> Interner<'a> {
+	pub fn new() -> Self {
+		return Interner {
+			map:   dashmap::DashMap::new(),
+			store: Vec::new(),
+		};
+	}
+
+	pub fn get(&self, key: Key) -> &str {
+		return self.store[key.0 as usize];
+	}
+
+	pub fn intern(&mut self, value: &'a str) -> Key {
+		if let Some(key) = self.map.get(&UniStr(value)) {
+			return *key;
+		}
+		let key = Key(self.store.len() as u32);
+		self.map.insert(UniStr(value), key);
+		self.store.push(value);
+		return key;
+	}
+}