full rewrite, kinda works

mers_lib/src/info/mod.rs

@@ -0,0 +1,58 @@
+use std::fmt::Debug;
+
+#[derive(Clone, Debug)]
+pub struct Info<L: Local> {
+    pub scopes: Vec<L>,
+}
+
+impl<L: Local> Info<L> {
+    /// Returns self, but completely empty (even without globals).
+    /// Only use this if you assume this Info will never be used.
+    pub fn neverused() -> Self {
+        Self { scopes: vec![] }
+    }
+}
+
+pub trait Local: Default + Debug {
+    type VariableIdentifier;
+    type VariableData;
+    // type TypesIdentifier;
+    // type TypesType;
+    fn init_var(&mut self, id: Self::VariableIdentifier, value: Self::VariableData);
+    fn get_var(&self, id: &Self::VariableIdentifier) -> Option<&Self::VariableData>;
+    fn get_var_mut(&mut self, id: &Self::VariableIdentifier) -> Option<&mut Self::VariableData>;
+    // fn add_type(&mut self, id: Self::TypesIdentifier, new_type: Self::TypesType);
+    // fn get_type(&self, id: Self::TypesIdentifier) -> Option<&Self::TypesType>;
+}
+
+impl<L: Local> Info<L> {
+    pub fn create_scope(&mut self) {
+        self.scopes.push(L::default())
+    }
+    /// WARNING: can remove the last scope, which can cause some other functions to panic. Use ONLY after a create_scope()
+    pub fn end_scope(&mut self) {
+        self.scopes.pop();
+    }
+}
+
+impl<L: Local> Local for Info<L> {
+    type VariableIdentifier = L::VariableIdentifier;
+    type VariableData = L::VariableData;
+    fn init_var(&mut self, id: Self::VariableIdentifier, value: Self::VariableData) {
+        self.scopes.last_mut().unwrap().init_var(id, value)
+    }
+    fn get_var(&self, id: &Self::VariableIdentifier) -> Option<&Self::VariableData> {
+        self.scopes.iter().find_map(|l| l.get_var(id))
+    }
+    fn get_var_mut(&mut self, id: &Self::VariableIdentifier) -> Option<&mut Self::VariableData> {
+        self.scopes.iter_mut().find_map(|l| l.get_var_mut(id))
+    }
+}
+
+impl<L: Local> Default for Info<L> {
+    fn default() -> Self {
+        Self {
+            scopes: vec![L::default()],
+        }
+    }
+}