feat(language): new continue keyword

Cargo.toml

@@ -7,11 +7,11 @@ edition = "2021"
 
 [dependencies]
 lazy_static = "1.4.0"
-pest = "2.0"
-pest_derive = "2.0"
+pest = "2.7.5"
+pest_derive = "2.7.5"
 # web
-egui = "0.20.0"
-eframe = { version = "0.20.0", default-features = false, features = [
+egui = "0.24.0"
+eframe = { version = "0.24.0", default-features = false, features = [
     "default_fonts", # Embed the default egui fonts.
     "glow",          # Use the glow rendering backend. Alternative: "wgpu".
 ] }
@@ -34,13 +34,13 @@ path = "src/web/main.rs"
 
 # native:
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
-tracing-subscriber = "0.3"
+tracing-subscriber = "0.3.18"
 
 # web:
 [target.'cfg(target_arch = "wasm32")'.dependencies]
-console_error_panic_hook = "0.1.6"
-tracing-wasm = "0.2"
-wasm-bindgen-futures = "0.4"
+console_error_panic_hook = "0.1.7"
+tracing-wasm = "0.2.1"
+wasm-bindgen-futures = "0.4.39"
 
 [profile.release]
 opt-level = 's'

README.md

@@ -13,6 +13,7 @@ Written in Rust with pest PEG parser.
 <br>
 
 ### TODO playground
+- compile time reading of the example file
 - syntax color
 - line numbers
 - better panel title
@@ -65,11 +66,11 @@ var: z => val: 8
 - read / write
 - program arguments
 - structs
-- iterator, for, continue keyword
+- iterator, for keyword
 - list
 - import from other files
 ### tools
-- live interpreter
+- repl
 - LLVM IR translation
 - JIT
 - compilation

example.duck

@@ -8,10 +8,12 @@ if (x) {
 	y = 5;
 	while (x) {
 		if (!y && z % 2) {
-			z = 8;
 			break;
-		} else if (y == 3) {
+		} else if (y == 3) { // never reached because of continue
 			z = 5;
+		} else if (y == 4) {
+			y = y - 2;
+			continue;
 		}
 		y = y - 1;
 	}

src/interpreter/duck_interpreter.rs

@@ -4,6 +4,7 @@ use std::{env, fs::File, io::Read};
 
 pub fn main() {
     for arg in env::args().skip(1) {
+        // if arg match --debug flag
         let mut f = File::open(&arg).unwrap_or_else(|_| panic!("file {} not found", arg));
         let mut content = String::new();
         f.read_to_string(&mut content)

src/interpreter/environment.rs

@@ -38,6 +38,6 @@ impl Display for Environment {
             .iter()
             .map(|(key, val)| format!("var: {0} => val: {1}", key, val))
             .collect();
-        write!(f, "{}", vars.join("\n"))
+        writeln!(f, "{}", vars.join("\n"))
     }
 }

src/interpreter/machine.rs

@@ -13,6 +13,7 @@ pub trait Execution {
 
 impl Execution for Stat {
     fn execute(&self, environment: &mut Environment) -> Result<ControlFlow, String> {
+        println!("statement: {}", &self);
         match *self {
             Stat::Condition(ref condition, ref consequence, ref alternative) => {
                 if condition.evaluate(environment)?.truth() {
@@ -43,9 +44,11 @@ impl Execution for Stat {
             Stat::Assignment(ref name, ref expr) => {
                 let value = expr.evaluate(environment)?;
                 environment.add(name, value);
+                println!("environment:\n{}", environment);
                 Ok(ControlFlow::Next)
             }
             Stat::Break => Ok(ControlFlow::Break),
+            Stat::Continue => Ok(ControlFlow::Next),
         }
     }
 }

src/parser/ast.rs

@@ -144,6 +144,12 @@ fn build_stat(pair: Pair<Rule>, in_loop: bool) -> Result<Box<Stat>, String> {
             }
             Err(parsing_error(pair, "break keyword while not in loop"))
         }
+        Rule::stat_continue => {
+            if in_loop {
+                return Ok(Stat::continue_keyword());
+            }
+            Err(parsing_error(pair, "continue keyword while not in loop"))
+        }
         rule => Err(format!(
             "statement expected assign, if, while or break, found {:?}",
             rule

src/parser/duck.pest

@@ -50,6 +50,7 @@ value = _{ boolean | number | variable | "(" ~ expr ~ ")" }
 term = { op_unary* ~ value }
 expr = { term ~ (op_binary ~ term)* }
 
+stat_continue = { "continue" ~ ";" }
 stat_break = { "break" ~ ";" }
 stat_assign = { variable ~ "=" ~ expr ~ ";" }
 stat_while = { "while" ~ "(" ~ expr ~ ")" ~ "{" ~ stats ~ "}" }
@@ -58,7 +59,7 @@ stat_elif = { ("else if" ~ "(" ~ expr ~ ")" ~ "{" ~ stats ~ "}" ~ "else" ~ "{" ~
 stat_if = { ("if" ~ "(" ~ expr ~ ")" ~ "{" ~ stats ~ "}" ~ "else" ~ "{" ~ stats ~ "}" ) |
             ("if" ~ "(" ~ expr ~ ")" ~ "{" ~ stats ~ "}" ~ (stat_elif)?) }
 
-stat = _{ ( stat_if | stat_while | stat_assign | stat_break ) }
+stat = _{ ( stat_if | stat_while | stat_assign | stat_break | stat_continue ) }
 
 stats = { (stat)* }
 

src/parser/syntax.rs

@@ -137,10 +137,9 @@ pub enum Stat {
     Loop(Box<Expr>, Vec<Stat>),
     Assignment(String, Box<Expr>),
     Break,
-    // continue
-    // declare
-    // call
-    // return
+    Continue, // declare
+              // call
+              // return
 }
 
 impl Stat {
@@ -150,6 +149,9 @@ impl Stat {
     pub fn break_keyword() -> Box<Stat> {
         Box::new(Stat::Break)
     }
+    pub fn continue_keyword() -> Box<Stat> {
+        Box::new(Stat::Continue)
+    }
     pub fn while_loop(condition: Box<Expr>, body: Vec<Stat>) -> Box<Stat> {
         Box::new(Stat::Loop(condition, body))
     }
@@ -168,7 +170,7 @@ impl Display for Stat {
             Stat::Condition(condition, body, else_body) => {
                 write!(f, "if {} {{", condition)?;
                 for statement in body {
-                    write!(f, "{}", statement)?;
+                    write!(f, " {} ", statement)?;
                 }
                 write!(f, "}}")?;
                 if let Some(else_body) = else_body {
@@ -189,6 +191,7 @@ impl Display for Stat {
             }
             Stat::Assignment(name, expr) => write!(f, "{} = {};", name, expr),
             Stat::Break => write!(f, "break;"),
+            Stat::Continue => write!(f, "continue;"),
         }
     }
 }

src/web/main.rs

@@ -1,16 +1,21 @@
 use ducklang::{interpreter::machine::Machine, parser::ast::build_ast};
 
-const EXAMPLE_CODE: &str = r#"// example code
+const EXAMPLE_CODE: &str = r#"/*
+An example of program with most of
+the supported features
+*/
 x = true;
 z = 3 + 4 * (2 + 1); // good order of op
 if (x) {
 	y = 5;
 	while (x) {
 		if (!y && z % 2) {
-			z = 8;
 			break;
-		} else if (y == 3) {
+		} else if (y == 3) { // never reached because of continue
 			z = 5;
+		} else if (y == 4) {
+			y = y - 2;
+			continue;
 		}
 		y = y - 1;
 	}
@@ -72,7 +77,7 @@ impl MyEguiApp {
             // calculate desired rows based on the height of the window
             let font_selection = egui::FontSelection::default();
             let font_id = font_selection.resolve(ui.style());
-            let row_height = ui.fonts().row_height(&font_id);
+            let row_height = ui.fonts(|fonts| fonts.row_height(&font_id));
             let rows = (ui.available_size().y / row_height) as usize;
             ui.add(
                 egui::TextEdit::multiline(&mut self.code)
@@ -164,11 +169,12 @@ fn main() {
 #[cfg(not(target_arch = "wasm32"))]
 fn main() {
     let options = eframe::NativeOptions {
-        initial_window_size: Some(egui::vec2(1280.0, 720.0)),
-        resizable: true,
+        viewport: egui::ViewportBuilder::default()
+            .with_inner_size([1280.0, 720.0])
+            .with_resizable(true),
         ..Default::default()
     };
-    eframe::run_native(
+    let _run_native = eframe::run_native(
         "Duckscript Playground",
         options,
         Box::new(|cc| Box::new(MyEguiApp::new(cc))),