Some more work on Wren parser

core/scripting/assets/scripts/wren/test01.wren

@@ -0,0 +1,2 @@
+// Hello, world!
+System.print("Hello, world!")

core/scripting/assets/scripts/wren/test02.wren

@@ -0,0 +1,10 @@
+// Compute the fibonacci number at position n
+fn fib(n) {
+  if (n <= 1) return n
+  return fib(n - 1) + fib(n - 2)
+}
+
+System.print("Fibonacci sequence:")
+for (i in 0..10) {
+  System.print("fib(%(_i)) = %(fib(i))")
+}

core/scripting/assets/scripts/wren/test03.wren

@@ -0,0 +1,81 @@
+// Conway's Game of Life
+class GameOfLife {
+  construct new(width, height) {
+    _width = width
+    _height = height
+    _grid = List.filled(width * height, false)
+  }
+
+  // Get cell at x,y coordinates
+  cell(x, y) {
+    if (x < 0 || x >= _width || y < 0 || y >= _height) return false
+    return _grid[y * _width + x]
+  }
+
+  // Set cell at x,y coordinates
+  setCell(x, y, value) {
+    if (x < 0 || x >= _width || y < 0 || y >= _height) return
+    _grid[y * _width + x] = value
+  }
+
+  // Count live neighbors for cell at x,y
+  countNeighbors(x, y) {
+    var count = 0
+    for (dy in -1..2) {
+      for (dx in -1..2) {
+        if (dx == 0 && dy == 0) continue
+        if (cell(x + dx, y + dy)) count = count + 1
+      }
+    }
+    return count
+  }
+
+  // Update the grid according to Game of Life rules
+  step() {
+    var newGrid = List.filled(_width * _height, false)
+
+    for (y in 0..._height) {
+      for (x in 0..._width) {
+        var neighbors = countNeighbors(x, y)
+        var alive = cell(x, y)
+
+        if (alive && (neighbors == 2 || neighbors == 3)) {
+          newGrid[y * _width + x] = true
+        } else if (!alive && neighbors == 3) {
+          newGrid[y * _width + x] = true
+        }
+      }
+    }
+
+    _grid = newGrid
+  }
+
+  // Display the current state
+  display() {
+    for (y in 0..._height) {
+      var line = ""
+      for (x in 0..._width) {
+        line = line + (cell(x, y) ? "■ " : "□ ")
+      }
+      System.print(line)
+    }
+    System.print("")
+  }
+}
+
+// Create a 10x10 game board
+var game = GameOfLife.new(10, 10)
+
+// Set up a simple glider pattern
+game.setCell(1, 0, true)
+game.setCell(2, 1, true)
+game.setCell(0, 2, true)
+game.setCell(1, 2, true)
+game.setCell(2, 2, true)
+
+// Run for 10 generations
+for (i in 0...10) {
+  System.print("Generation %(i):")
+  game.display()
+  game.step()
+}

core/scripting/src/lang/wren.rs

@@ -79,11 +79,6 @@ pub enum Keyword {
   Super,
 }
 
-/// Parses a list of tokens into an AST [`Expression`].
-pub fn parse(code: &str) -> Result<Expression, ParseError> {
-  Parser::from_code(code).parse_expression()
-}
-
 /// A parser for Wren code.
 struct Parser {
   tokens: Vec<Token>,
@@ -181,6 +176,11 @@ impl Parser {
   }
 }
 
+/// Parses a string of Wren code into an AST [`Expression`].
+pub fn parse(code: &str) -> Result<Expression, ParseError> {
+  Parser::from_code(code).parse_expression()
+}
+
 /// Tokenises a string of Wren code into a list of [`Token`]s.
 fn tokenise(code: &str) -> Vec<Token> {
   let mut tokens = Vec::new();
@@ -214,7 +214,30 @@ fn tokenise(code: &str) -> Vec<Token> {
           }
           continue;
         }
-        None => Token::Operator(Operator::Divide),
+        None => match characters.next_if_eq(&(position + 1, '*')) {
+          Some(_) => {
+            // ignore block comments
+            let mut depth = 1;
+            while depth > 0 {
+              match characters.next() {
+                Some((_, '*')) => {
+                  if let Some((_, '/')) = characters.next() {
+                    depth -= 1;
+                  }
+                }
+                Some((_, '/')) => {
+                  if let Some((_, '*')) = characters.next() {
+                    depth += 1;
+                  }
+                }
+                None => break, // Unterminated block comment
+                _ => {}
+              }
+            }
+            continue;
+          }
+          None => Token::Operator(Operator::Divide),
+        },
       },
       '<' => match characters.next_if_eq(&(position + 1, '=')) {
         Some(_) => Token::Operator(Operator::LessThanOrEqual),
@@ -458,4 +481,28 @@ mod tests {
       ))
     )
   );
+
+  macro_rules! parse_file_test {
+    ($name:ident, $path:expr) => {
+      #[test]
+      fn $name() {
+        use std::fs;
+        let contents = fs::read_to_string($path).expect("Failed to read file");
+        let result = parse(&contents);
+
+        assert!(
+          result.is_ok(),
+          "Failed to parse file {}: {:?}",
+          $path,
+          result.err()
+        );
+      }
+    };
+  }
+
+  // parse_file_test!(it_should_parse_test01,
+  // "assets/scripts/wren/test01.wren"); parse_file_test!
+  // (it_should_parse_test02, "assets/scripts/wren/test02.wren");
+  // parse_file_test!(it_should_parse_test03,
+  // "assets/scripts/wren/test03.wren");
 }