mers rewrite is starting to be usable

mers_lib/src/program/run/mod.rs

@@ -1,4 +1,7 @@
-use std::sync::Arc;
+use std::{
+    fmt::{Debug, Display},
+    sync::{Arc, Mutex},
+};
 
 use crate::{
     data::{self, Data, Type},
@@ -16,21 +19,31 @@ pub mod function;
 #[cfg(feature = "run")]
 pub mod r#if;
 #[cfg(feature = "run")]
-pub mod r#loop;
-#[cfg(feature = "run")]
-pub mod switch;
-#[cfg(feature = "run")]
 pub mod tuple;
 #[cfg(feature = "run")]
 pub mod value;
 #[cfg(feature = "run")]
 pub mod variable;
 
-pub trait MersStatement: std::fmt::Debug {
+pub trait MersStatement: Debug + Send + Sync {
+    fn check_custom(
+        &self,
+        info: &mut CheckInfo,
+        init_to: Option<&Type>,
+    ) -> Result<Type, CheckError>;
     fn run_custom(&self, info: &mut Info) -> Data;
     /// if true, local variables etc. will be contained inside their own scope.
     fn has_scope(&self) -> bool;
-    // fn outputs(&self) -> Type;
+    fn check(&self, info: &mut CheckInfo, assign: Option<&Type>) -> Result<Type, CheckError> {
+        if self.has_scope() {
+            info.create_scope();
+        }
+        let o = self.check_custom(info, assign);
+        if self.has_scope() {
+            info.end_scope();
+        }
+        o
+    }
     fn run(&self, info: &mut Info) -> Data {
         if self.has_scope() {
             info.create_scope();
@@ -43,18 +56,54 @@ pub trait MersStatement: std::fmt::Debug {
     }
 }
 
+#[derive(Clone, Debug)]
+pub struct CheckError(pub String);
+impl Display for CheckError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "{}", self.0)
+    }
+}
+
 pub type Info = info::Info<Local>;
+pub type CheckInfo = info::Info<CheckLocal>;
 
 #[derive(Default, Clone, Debug)]
 pub struct Local {
-    vars: Vec<Data>,
+    vars: Vec<Arc<Mutex<Data>>>,
+}
+#[derive(Default, Clone, Debug)]
+pub struct CheckLocal {
+    vars: Vec<Type>,
 }
 impl info::Local for Local {
     type VariableIdentifier = usize;
-    type VariableData = Data;
+    type VariableData = Arc<Mutex<Data>>;
     fn init_var(&mut self, id: Self::VariableIdentifier, value: Self::VariableData) {
+        let nothing = Arc::new(Mutex::new(Data::new(data::bool::Bool(false))));
         while self.vars.len() <= id {
-            self.vars.push(Data::new(data::bool::Bool(false)));
+            self.vars.push(Arc::clone(&nothing));
+        }
+        self.vars[id] = value;
+    }
+    fn get_var(&self, id: &Self::VariableIdentifier) -> Option<&Self::VariableData> {
+        match self.vars.get(*id) {
+            Some(v) => Some(v),
+            None => None,
+        }
+    }
+    fn get_var_mut(&mut self, id: &Self::VariableIdentifier) -> Option<&mut Self::VariableData> {
+        match self.vars.get_mut(*id) {
+            Some(v) => Some(v),
+            None => None,
+        }
+    }
+}
+impl info::Local for CheckLocal {
+    type VariableIdentifier = usize;
+    type VariableData = Type;
+    fn init_var(&mut self, id: Self::VariableIdentifier, value: Self::VariableData) {
+        while self.vars.len() <= id {
+            self.vars.push(Type::empty());
         }
         self.vars[id] = value;
     }