Rename dir: compiler -> crates

crates/erg_compiler/module/index.rs

@@ -0,0 +1,73 @@
+use std::collections::hash_map::{Keys, Values};
+use std::fmt;
+
+use erg_common::dict::Dict;
+use erg_common::set;
+use erg_common::set::Set;
+use erg_common::shared::Shared;
+
+use crate::varinfo::AbsLocation;
+
+#[derive(Debug, Clone, Default)]
+pub struct ModuleIndex {
+    attrs: Dict<AbsLocation, Set<AbsLocation>>,
+}
+
+impl fmt::Display for ModuleIndex {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.attrs.fmt(f)
+    }
+}
+
+impl ModuleIndex {
+    pub fn new() -> Self {
+        Self { attrs: Dict::new() }
+    }
+
+    pub fn add_ref(&mut self, referee: AbsLocation, referrer: AbsLocation) {
+        if let Some(referrers) = self.attrs.get_mut(&referee) {
+            referrers.insert(referrer);
+        } else {
+            self.attrs.insert(referee, set! {referrer});
+        }
+    }
+
+    pub fn get_refs(&self, referee: &AbsLocation) -> Option<&Set<AbsLocation>> {
+        self.attrs.get(referee)
+    }
+}
+
+#[derive(Debug, Clone, Default)]
+pub struct SharedModuleIndex(Shared<ModuleIndex>);
+
+impl fmt::Display for SharedModuleIndex {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.borrow().fmt(f)
+    }
+}
+
+impl SharedModuleIndex {
+    pub fn new() -> Self {
+        Self(Shared::new(ModuleIndex::new()))
+    }
+
+    pub fn add_ref(&self, referee: AbsLocation, referrer: AbsLocation) {
+        self.0.borrow_mut().add_ref(referee, referrer);
+    }
+
+    pub fn get_refs(&self, referee: &AbsLocation) -> Option<&Set<AbsLocation>> {
+        unsafe { self.0.as_ptr().as_ref().unwrap().get_refs(referee) }
+    }
+
+    pub fn referees(&self) -> Keys<AbsLocation, Set<AbsLocation>> {
+        unsafe { self.0.as_ptr().as_ref().unwrap().attrs.keys() }
+    }
+
+    pub fn referrers(&self) -> Values<AbsLocation, Set<AbsLocation>> {
+        unsafe { self.0.as_ptr().as_ref().unwrap().attrs.values() }
+    }
+
+    pub fn initialize(&self) {
+        self.0.borrow_mut().attrs.clear();
+    }
+}