Move reference counted rw lock for list values

src/abstract_tree/for.rs

@@ -1,3 +1,5 @@
+use std::sync::RwLock;
+
 use rayon::prelude::*;
 use serde::{Deserialize, Serialize};
 use tree_sitter::Node;
@@ -54,21 +56,26 @@ impl AbstractTree for For {
         let key = self.item_id.inner();
 
         if self.is_async {
+            let context = RwLock::new(context);
+
             values.par_iter().try_for_each(|value| {
-                let mut iter_context = Map::clone_from(context)?;
+                let mut context = match context.write() {
+                    Ok(map) => map,
+                    Err(error) => return Err(error.into()),
+                };
 
-                iter_context.set(key.clone(), value.clone(), None);
-
-                self.block.run(source, &mut iter_context).map(|_value| ())
+                context.set(key.clone(), value.clone(), None);
+                self.block.run(source, &mut context).map(|_value| ())
             })?;
+
+            context.write()?.set(key.clone(), Value::none(), None);
         } else {
-            let mut loop_context = Map::clone_from(context)?;
-
             for value in values.iter() {
-                loop_context.set(key.clone(), value.clone(), None);
-
-                self.block.run(source, &mut loop_context)?;
+                context.set(key.clone(), value.clone(), None);
+                self.block.run(source, context)?;
             }
+
+            context.set(key.clone(), Value::none(), None);
         }
 
         Ok(Value::none())

src/abstract_tree/identifier.rs

@@ -35,6 +35,10 @@ impl AbstractTree for Identifier {
         Ok(Identifier(text.to_string()))
     }
 
+    fn check_type(&self, _source: &str, _context: &Map) -> Result<()> {
+        Ok(())
+    }
+
     fn run(&self, _source: &str, context: &mut Map) -> Result<Value> {
         if let Some((value, _)) = context.variables().get(&self.0) {
             Ok(value.clone())
@@ -43,10 +47,6 @@ impl AbstractTree for Identifier {
         }
     }
 
-    fn check_type(&self, _source: &str, _context: &Map) -> Result<()> {
-        Ok(())
-    }
-
     fn expected_type(&self, context: &Map) -> Result<Type> {
         if let Some((_value, r#type)) = context.variables().get(&self.0) {
             Ok(r#type.clone())

src/bin/gui/app.rs

@@ -6,21 +6,21 @@ use egui_extras::{Column, TableBuilder};
 use serde::{Deserialize, Serialize};
 
 #[derive(Deserialize, Serialize)]
-pub struct App {
+pub struct App<'c> {
     path: String,
     source: String,
     context: Map,
     #[serde(skip)]
-    interpreter: Interpreter,
+    interpreter: Interpreter<'c>,
     output: Result<Value>,
     error: Option<String>,
 }
 
-impl App {
+impl<'c> App<'c> {
     pub fn new(cc: &eframe::CreationContext<'_>, path: PathBuf) -> Self {
-        fn create_app(path: PathBuf) -> App {
+        fn create_app<'c>(path: PathBuf) -> App<'c> {
             let context = Map::new();
-            let mut interpreter = Interpreter::new(context.clone());
+            let mut interpreter = Interpreter::new(&mut context);
             let read_source = read_to_string(&path);
             let source = if let Ok(source) = read_source {
                 source
@@ -54,7 +54,7 @@ impl App {
     }
 }
 
-impl eframe::App for App {
+impl<'c> eframe::App for App<'c> {
     /// Called by the frame work to save state before shutdown.
     fn save(&mut self, storage: &mut dyn eframe::Storage) {
         eframe::set_value(storage, eframe::APP_KEY, self);

src/interpret.rs

@@ -18,7 +18,7 @@ use crate::{language, AbstractTree, Error, Map, Result, Root, Value};
 /// assert_eq!(interpret("1 + 2 + 3"), Ok(Value::Integer(6)));
 /// ```
 pub fn interpret(source: &str) -> Result<Value> {
-    interpret_with_context(source, Map::new())
+    interpret_with_context(source, &mut Map::new())
 }
 
 /// Interpret the given source code with the given context.
@@ -40,7 +40,7 @@ pub fn interpret(source: &str) -> Result<Value> {
 ///     Ok(Value::Integer(10))
 /// );
 /// ```
-pub fn interpret_with_context(source: &str, context: Map) -> Result<Value> {
+pub fn interpret_with_context(source: &str, context: &mut Map) -> Result<Value> {
     let mut interpreter = Interpreter::new(context);
     let value = interpreter.run(source)?;
 
@@ -48,15 +48,15 @@ pub fn interpret_with_context(source: &str, context: Map) -> Result<Value> {
 }
 
 /// A source code interpreter for the Dust language.
-pub struct Interpreter {
+pub struct Interpreter<'c> {
     parser: Parser,
-    context: Map,
+    context: &'c mut Map,
     syntax_tree: Option<TSTree>,
     abstract_tree: Option<Root>,
 }
 
-impl Interpreter {
-    pub fn new(context: Map) -> Self {
+impl<'c> Interpreter<'c> {
+    pub fn new(context: &'c mut Map) -> Self {
         let mut parser = Parser::new();
 
         parser
@@ -71,6 +71,14 @@ impl Interpreter {
         }
     }
 
+    pub fn context(&self) -> &Map {
+        &self.context
+    }
+
+    pub fn context_mut(&mut self) -> &mut Map {
+        &mut self.context
+    }
+
     pub fn parse(&mut self, source: &str) -> Result<()> {
         fn check_for_error(source: &str, node: Node, cursor: &mut TreeCursor) -> Result<()> {
             if node.is_error() {
@@ -101,14 +109,14 @@ impl Interpreter {
         Ok(())
     }
 
-    pub fn run(&mut self, source: &str) -> Result<Value> {
+    pub fn run(&'c mut self, source: &str) -> Result<Value> {
         self.parse(source)?;
 
         self.abstract_tree = if let Some(syntax_tree) = &self.syntax_tree {
             Some(Root::from_syntax_node(
                 source,
                 syntax_tree.root_node(),
-                &mut self.context,
+                self.context,
             )?)
         } else {
             return Err(Error::ParserCancelled);
@@ -130,9 +138,3 @@ impl Interpreter {
         }
     }
 }
-
-impl Default for Interpreter {
-    fn default() -> Self {
-        Interpreter::new(Map::new())
-    }
-}

src/main.rs

@@ -72,7 +72,7 @@ fn main() {
     let mut parser = TSParser::new();
     parser.set_language(language()).unwrap();
 
-    let mut interpreter = Interpreter::new(context);
+    let mut interpreter = Interpreter::new(&mut context);
 
     if args.show_syntax_tree {
         interpreter.parse(&source).unwrap();
@@ -168,7 +168,7 @@ impl Highlighter for DustReadline {
 }
 
 fn run_cli_shell() {
-    let context = Map::new();
+    let mut context = Map::new();
     let mut rl: Editor<DustReadline, DefaultHistory> = Editor::new().unwrap();
 
     rl.set_helper(Some(DustReadline::new()));
@@ -185,7 +185,7 @@ fn run_cli_shell() {
 
                 rl.add_history_entry(line).unwrap();
 
-                let eval_result = interpret_with_context(line, context.clone());
+                let eval_result = interpret_with_context(line, &mut context);
 
                 match eval_result {
                     Ok(value) => println!("{value}"),

src/value/list.rs

@@ -1,13 +1,12 @@
 use std::{
     cmp::Ordering,
     fmt::{self, Display, Formatter},
-    sync::{Arc, RwLock, RwLockReadGuard, RwLockWriteGuard},
 };
 
 use crate::Value;
 
 #[derive(Debug, Clone)]
-pub struct List(Arc<RwLock<Vec<Value>>>);
+pub struct List(Vec<Value>);
 
 impl Default for List {
     fn default() -> Self {
@@ -17,23 +16,23 @@ impl Default for List {
 
 impl List {
     pub fn new() -> Self {
-        List(Arc::new(RwLock::new(Vec::new())))
+        List(Vec::new())
     }
 
     pub fn with_capacity(capacity: usize) -> Self {
-        List(Arc::new(RwLock::new(Vec::with_capacity(capacity))))
+        List(Vec::with_capacity(capacity))
     }
 
     pub fn with_items(items: Vec<Value>) -> Self {
-        List(Arc::new(RwLock::new(items)))
+        List(items)
     }
 
-    pub fn items(&self) -> RwLockReadGuard<'_, Vec<Value>> {
-        self.0.read().unwrap()
+    pub fn items(&self) -> &Vec<Value> {
+        &self.0
     }
 
-    pub fn items_mut(&self) -> RwLockWriteGuard<'_, Vec<Value>> {
-        self.0.write().unwrap()
+    pub fn items_mut(&mut self) -> &mut Vec<Value> {
+        &mut self.0
     }
 }
 
@@ -41,19 +40,13 @@ impl Eq for List {}
 
 impl PartialEq for List {
     fn eq(&self, other: &Self) -> bool {
-        let left = self.0.read().unwrap().clone().into_iter();
-        let right = other.0.read().unwrap().clone().into_iter();
-
-        left.eq(right)
+        self.0.eq(&other.0)
     }
 }
 
 impl Ord for List {
     fn cmp(&self, other: &Self) -> Ordering {
-        let left = self.0.read().unwrap().clone().into_iter();
-        let right = other.0.read().unwrap().clone().into_iter();
-
-        left.cmp(right)
+        self.0.cmp(&other.0)
     }
 }
 

tests/interpret.rs

@@ -76,6 +76,19 @@ mod for_loop {
             result
         );
     }
+
+    #[test]
+    fn async_modify_value() {
+        let result = interpret(
+            "
+            list = []
+            async for i in [1 2 3] { list += i }
+            length(list)
+            ",
+        );
+
+        assert_eq!(Ok(Value::Integer(3)), result);
+    }
 }
 
 mod logic {