Reorganize name resolution

1 files changed, 78 insertions, 0 deletions

diff --git a/crates/ra_hir/src/nameres/per_ns.rs b/crates/ra_hir/src/nameres/per_ns.rs
new file mode 100644
index 000000000..c40a3ff9d
--- /dev/null
+++ b/crates/ra_hir/src/nameres/per_ns.rs
@@ -0,0 +1,78 @@
+#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum Namespace {
+    Types,
+    Values,
+}
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+pub struct PerNs<T> {
+    pub types: Option<T>,
+    pub values: Option<T>,
+}
+
+impl<T> Default for PerNs<T> {
+    fn default() -> Self {
+        PerNs { types: None, values: None }
+    }
+}
+
+impl<T> PerNs<T> {
+    pub fn none() -> PerNs<T> {
+        PerNs { types: None, values: None }
+    }
+
+    pub fn values(t: T) -> PerNs<T> {
+        PerNs { types: None, values: Some(t) }
+    }
+
+    pub fn types(t: T) -> PerNs<T> {
+        PerNs { types: Some(t), values: None }
+    }
+
+    pub fn both(types: T, values: T) -> PerNs<T> {
+        PerNs { types: Some(types), values: Some(values) }
+    }
+
+    pub fn is_none(&self) -> bool {
+        self.types.is_none() && self.values.is_none()
+    }
+
+    pub fn is_both(&self) -> bool {
+        self.types.is_some() && self.values.is_some()
+    }
+
+    pub fn take(self, namespace: Namespace) -> Option<T> {
+        match namespace {
+            Namespace::Types => self.types,
+            Namespace::Values => self.values,
+        }
+    }
+
+    pub fn take_types(self) -> Option<T> {
+        self.take(Namespace::Types)
+    }
+
+    pub fn take_values(self) -> Option<T> {
+        self.take(Namespace::Values)
+    }
+
+    pub fn get(&self, namespace: Namespace) -> Option<&T> {
+        self.as_ref().take(namespace)
+    }
+
+    pub fn as_ref(&self) -> PerNs<&T> {
+        PerNs { types: self.types.as_ref(), values: self.values.as_ref() }
+    }
+
+    pub fn or(self, other: PerNs<T>) -> PerNs<T> {
+        PerNs { types: self.types.or(other.types), values: self.values.or(other.values) }
+    }
+
+    pub fn and_then<U>(self, f: impl Fn(T) -> Option<U>) -> PerNs<U> {
+        PerNs { types: self.types.and_then(&f), values: self.values.and_then(&f) }
+    }
+
+    pub fn map<U>(self, f: impl Fn(T) -> U) -> PerNs<U> {
+        PerNs { types: self.types.map(&f), values: self.values.map(&f) }
+    }
+}