- refactored lexer

- updated lexer to allow hex and binary integer literals
- updated parser with support for writing to pointers
- updated code generation to support writing to pointers
- fixed a bug with codegen where args are loaded from incorrect offsets
  due to saving registers prior to calling.

compiler/src/codegen.rs

@@ -29,8 +29,10 @@ static GLOBAL_METHODS: LazyLock<HashMap<&str, &str>> = LazyLock::new(|| {
         ("println", "print::println"),
         ("printnum", "print::print_num"),
         ("print_space", "print::print_whitespace"),
+        ("print_newline", "print::print_newline"),
         ("print_char", "print::print_byte"),
         ("print_word", "print::print_word"),
+        ("print_hex", "print::print_hex_word"),
     ])
 });
 
@@ -252,6 +254,19 @@ impl CodeGenerator {
             Statement::Break => unimplemented!(),
             Statement::Continue => unimplemented!(),
 
+            Statement::PtrWrite { ptr, value } => {
+                let (result_reg, expr_code) = self.generate_expression(value, true)?;
+                code.extend(expr_code);
+
+                let (ptr_reg, ptr_code) = self.generate_expression(ptr, true)?;
+                code.extend(ptr_code);
+
+                code.push(format!("\tstw {}, {}", result_reg, ptr_reg));
+
+                self.allocator.free_temp(&result_reg);
+                self.allocator.free_temp(&ptr_reg);
+            }
+
             Statement::Assign { varname, value } => {
                 // Evaluate expression
                 let (result_reg, expr_code) = self.generate_expression(value, true)?;
@@ -540,6 +555,14 @@ impl CodeGenerator {
             }
 
             Expression::Call { name, args } => {
+                // first evaluate all the args we're going to need
+                let mut arg_regs = Vec::new();
+                for arg in args.iter().rev() {
+                    let (arg_reg, arg_code) = self.generate_expression(arg, true)?;
+                    code.extend(arg_code);
+                    arg_regs.push(arg_reg);
+                }
+
                 // Save caller-saved registers and track which ones we saved
                 let saved_regs = self.allocator.get_caller_saved_registers();
                 for reg in &saved_regs {
@@ -547,12 +570,12 @@ impl CodeGenerator {
                 }
 
                 // Evaluate and push arguments in reverse order
-                let mut arg_regs = Vec::new();
+                for (i, arg_reg) in arg_regs.iter().enumerate() {
-                for arg in args.iter().rev() {
+                    code.push(format!(
-                    let (arg_reg, arg_code) = self.generate_expression(arg, true)?;
+                        "\tpush {} // push arg {}",
-                    code.extend(arg_code);
+                        arg_reg,
-                    code.push(format!("\tpush {}", arg_reg));
+                        args.len() - 1 - i
-                    arg_regs.push(arg_reg);
+                    ));
                 }
 
                 if GLOBAL_METHODS.contains_key(name.name.as_str()) {
@@ -564,10 +587,11 @@ impl CodeGenerator {
                     return Err(CompilerError::Undefined(name.clone()));
                 }
 
-                let result_reg = String::new();
+                let result_reg: String;
 
                 if use_result {
-                    let (result_reg, result_alloc) = self.allocator.alloc_temp()?;
+                    let (temp_result_reg, result_alloc) = self.allocator.alloc_temp()?;
+                    result_reg = temp_result_reg;
 
                     code.extend(result_alloc);
                     code.push(format!("\tpop {}", result_reg));
@@ -579,6 +603,8 @@ impl CodeGenerator {
                         }
                     }
                 } else {
+                    result_reg = "zero".to_string();
+
                     // Clean up arguments
                     if args.len() > 0 {
                         for _ in 0..(args.len()) {

compiler/src/lexer.rs

@@ -20,7 +20,7 @@ pub enum Token {
     // Identifiers and literals
     Identifier(String),
     String(String),
-    Integer(u32),
+    Integer(u64),
     Char(char),
 
     // Symbols
@@ -31,13 +31,12 @@ pub enum Token {
     Semicolon,  // ;
     Colon,      // :
     Comma,      // ,
-    // Pipe,       // |
 
     // Operators
-    Plus,  // +
+    Plus,         // +
-    Minus, // -
+    Minus,        // -
-    Star,  // *
+    Star,         // *
-    Amphersand,
+    Amphersand,   // &
     Slash,        // /
     Assign,       // =
     EqualEqual,   // ==
@@ -80,7 +79,6 @@ impl Token {
             Token::Colon => "Colon",
             Token::Comma => "Comma",
             Token::RightArrow => "RightArrow",
-            // Token::Pipe => "Pipe",
             Token::Plus => "Plus",
             Token::Minus => "Minus",
             Token::Star => "Star",
@@ -139,30 +137,258 @@ impl<'a> Lexer<'a> {
         }
     }
 
+    fn skip_line_comment(&mut self) {
+        // Skip the two slashes
+        self.advance(); // first /
+        self.advance(); // second /
+
+        // Skip until newline or EOF
+        while let Some(c) = self.current {
+            if c == '\n' {
+                self.line += 1;
+                self.advance();
+                break;
+            }
+            self.advance();
+        }
+    }
+
+    fn skip_block_comment(&mut self) -> Result<(), String> {
+        // Skip the /*
+        self.advance(); // /
+        self.advance(); // *
+
+        let start_line = self.line;
+
+        // Look for */
+        while let Some(c) = self.current {
+            if c == '\n' {
+                self.line += 1;
+            }
+
+            if c == '*' {
+                if let Some(&next) = self.peek() {
+                    if next == '/' {
+                        self.advance(); // *
+                        self.advance(); // /
+                        return Ok(());
+                    }
+                }
+            }
+
+            self.advance();
+        }
+
+        Err(format!(
+            "Unterminated block comment starting at line {}",
+            start_line
+        ))
+    }
+
+    fn skip_whitespace_and_comments(&mut self) {
+        loop {
+            self.skip_whitespace();
+
+            // Check for comments
+            if let Some('/') = self.current {
+                if let Some(&next) = self.peek() {
+                    match next {
+                        '/' => {
+                            self.skip_line_comment();
+                            continue;
+                        }
+                        '*' => {
+                            if let Err(e) = self.skip_block_comment() {
+                                eprintln!("Lexer error: {}", e);
+                            }
+                            continue;
+                        }
+                        _ => break,
+                    }
+                }
+            }
+
+            break;
+        }
+    }
+
     fn read_identifier(&mut self) -> String {
         let mut ident = String::new();
+
+        // Include the current character if it's valid
+        if let Some(c) = self.current {
+            if c.is_alphabetic() || c == '_' {
+                ident.push(c);
+            }
+        }
+
+        // Read remaining characters
         while let Some(&c) = self.peek() {
             if c.is_alphanumeric() || c == '_' {
-                ident.push(c);
                 self.advance();
+                ident.push(c);
             } else {
                 break;
             }
         }
+
         ident
     }
 
-    fn read_number(&mut self) -> i64 {
+    fn keyword_or_identifier(&mut self) -> Token {
-        let mut num_str = String::from(self.current.unwrap());
+        let ident = self.read_identifier();
+
+        match ident.as_str() {
+            "fn" => Token::Fn,
+            "if" => Token::If,
+            "else" => Token::Else,
+            "while" => Token::While,
+            "loop" => Token::Loop,
+            "break" => Token::Break,
+            "return" => Token::Return,
+            "continue" => Token::Continue,
+            "include" => Token::Include,
+            "let" => Token::Let,
+            "const" => Token::Const,
+            "static" => Token::Static,
+            _ => Token::Identifier(ident),
+        }
+    }
+
+    fn read_number(&mut self) -> Result<u64, String> {
+        let current = self.current.unwrap();
+
+        // Check for hex (0x) or binary (0b) prefix
+        if current == '0' {
+            if let Some(&next_char) = self.peek() {
+                match next_char {
+                    'x' | 'X' => {
+                        self.advance(); // consume '0'
+                        self.advance(); // consume 'x'
+                        return self.read_hex_number();
+                    }
+                    'b' | 'B' => {
+                        self.advance(); // consume '0'
+                        self.advance(); // consume 'b'
+                        return self.read_binary_number();
+                    }
+                    _ => {}
+                }
+            }
+        }
+
+        // Read decimal number
+        self.read_decimal_number()
+    }
+
+    fn read_decimal_number(&mut self) -> Result<u64, String> {
+        let mut num_str = String::new();
+
+        if let Some(c) = self.current {
+            num_str.push(c);
+        }
+
         while let Some(&c) = self.peek() {
             if c.is_ascii_digit() {
-                num_str.push(c);
                 self.advance();
+                num_str.push(c);
             } else {
                 break;
             }
         }
-        num_str.parse().unwrap()
+
+        num_str
+            .parse::<u64>()
+            .map_err(|_| format!("Invalid decimal number: {}", num_str))
+    }
+
+    fn read_hex_number(&mut self) -> Result<u64, String> {
+        let mut num_str = String::new();
+
+        // Read current character if it's a hex digit
+        if let Some(c) = self.current {
+            if c.is_ascii_hexdigit() {
+                num_str.push(c);
+            }
+        }
+
+        while let Some(&c) = self.peek() {
+            if c.is_ascii_hexdigit() {
+                self.advance();
+                num_str.push(c);
+            } else {
+                break;
+            }
+        }
+
+        if num_str.is_empty() {
+            return Err("Invalid hexadecimal number: no digits after 0x".to_string());
+        }
+
+        u64::from_str_radix(&num_str, 16)
+            .map_err(|_| format!("Invalid hexadecimal number: {}", num_str))
+    }
+
+    fn read_binary_number(&mut self) -> Result<u64, String> {
+        let mut num_str = String::new();
+
+        // Read current character if it's a binary digit
+        if let Some(c) = self.current {
+            if c == '0' || c == '1' {
+                num_str.push(c);
+            }
+        }
+
+        while let Some(&c) = self.peek() {
+            if c == '0' || c == '1' {
+                self.advance();
+                num_str.push(c);
+            } else {
+                break;
+            }
+        }
+
+        if num_str.is_empty() {
+            return Err("Invalid binary number: no digits after 0b".to_string());
+        }
+
+        u64::from_str_radix(&num_str, 2)
+            .map_err(|_| format!("Invalid binary number: {}", num_str))
+    }
+
+    fn read_string(&mut self) -> Result<String, String> {
+        self.advance(); // Skip the opening quote
+        let mut s = String::new();
+
+        while let Some(c) = self.current {
+            if c == '"' {
+                return Ok(s);
+            }
+
+            // Handle escape sequences
+            if c == '\\' {
+                self.advance();
+                if let Some(escaped) = self.current {
+                    let escaped_char = match escaped {
+                        'n' => '\n',
+                        't' => '\t',
+                        'r' => '\r',
+                        '\\' => '\\',
+                        '"' => '"',
+                        _ => escaped, // For now, just use the character as-is
+                    };
+                    s.push(escaped_char);
+                } else {
+                    return Err("Unexpected end of string after escape".to_string());
+                }
+            } else {
+                s.push(c);
+            }
+
+            self.advance();
+        }
+
+        Err("Unterminated string literal".to_string())
     }
 
     fn match_next(&mut self, expected: char) -> bool {
@@ -175,104 +401,140 @@ impl<'a> Lexer<'a> {
         }
     }
 
-    pub fn next_token(&mut self) -> Token {
+    fn scan_single_char_token(&mut self, c: char) -> Option<Token> {
-        self.skip_whitespace();
+        match c {
+            '(' => Some(Token::LeftParen),
+            ')' => Some(Token::RightParen),
+            '{' => Some(Token::LeftBrace),
+            '}' => Some(Token::RightBrace),
+            ';' => Some(Token::Semicolon),
+            ':' => Some(Token::Colon),
+            ',' => Some(Token::Comma),
+            '&' => Some(Token::Amphersand),
+            '+' => Some(Token::Plus),
+            '*' => Some(Token::Star),
+            _ => None,
+        }
+    }
 
-        let token = match self.current {
+    fn scan_operator(&mut self, c: char) -> Option<Token> {
-            Some('(') => Token::LeftParen,
+        match c {
-            Some(')') => Token::RightParen,
+            '-' => Some(if self.match_next('>') {
-            Some('{') => Token::LeftBrace,
+                Token::RightArrow
-            Some('}') => Token::RightBrace,
+            } else {
-            Some(';') => Token::Semicolon,
+                Token::Minus
-            Some(':') => Token::Colon,
+            }),
-            Some(',') => Token::Comma,
+            '!' => Some(if self.match_next('=') {
-            Some('&') => Token::Amphersand,
+                Token::BangEqual
-            // Some('|') => Token::Pipe,
+            } else {
-            Some('+') => Token::Plus,
+                Token::Bang
-            Some('*') => Token::Star,
+            }),
-            Some('/') => Token::Slash,
+            '=' => Some(if self.match_next('=') {
-            Some('-') => {
+                Token::EqualEqual
-                if self.match_next('>') {
+            } else {
-                    Token::RightArrow
+                Token::Assign
-                } else {
+            }),
-                    Token::Minus
+            '<' => Some(if self.match_next('=') {
-                }
+                Token::LessEqual
-            }
+            } else {
-            Some('!') => {
+                Token::Less
-                if self.match_next('=') {
+            }),
-                    Token::BangEqual
+            '>' => Some(if self.match_next('=') {
-                } else {
+                Token::GreaterEqual
-                    Token::Bang
+            } else {
-                }
+                Token::Greater
-            }
+            }),
-            Some('=') => {
+            '/' => {
-                if self.match_next('=') {
+                // Check if it's a comment or division
-                    Token::EqualEqual
+                if let Some(&next) = self.peek() {
-                } else {
+                    if next == '/' || next == '*' {
-                    Token::Assign
+                        // It's a comment, don't consume it here
-                }
+                        // Let skip_whitespace_and_comments handle it
-            }
+                        None
-            Some('<') => {
+                    } else {
-                if self.match_next('=') {
+                        Some(Token::Slash)
-                    Token::LessEqual
-                } else {
-                    Token::Less
-                }
-            }
-            Some('>') => {
-                if self.match_next('=') {
-                    Token::GreaterEqual
-                } else {
-                    Token::Greater
-                }
-            }
-            Some('"') => {
-                self.advance(); // Skip the opening quote
-                let mut s = String::new();
-                while let Some(c) = self.current {
-                    if c == '"' {
-                        break;
                     }
-                    s.push(c);
-                    self.advance();
-                }
-                Token::String(s)
-            }
-            Some(c) => {
-                if c.is_alphabetic() || c == '_' {
-                    let mut ident = c.to_string();
-                    ident.push_str(&self.read_identifier());
-                    match ident.as_str() {
-                        "fn" => Token::Fn,
-                        "if" => Token::If,
-                        "else" => Token::Else,
-                        "while" => Token::While,
-                        "loop" => Token::Loop,
-                        "break" => Token::Break,
-                        "return" => Token::Return,
-                        "continue" => Token::Continue,
-                        "include" => Token::Include,
-                        "let" => Token::Let,
-                        "const" => Token::Const,
-                        "static" => Token::Static,
-                        _ => Token::Identifier(ident),
-                    }
-                } else if c.is_ascii_digit() {
-                    Token::Integer(self.read_number() as u32)
                 } else {
-                    // Skip unknown characters for now
+                    Some(Token::Slash)
-                    self.advance();
-                    return self.next_token();
                 }
             }
-            None => Token::Eof,
+            _ => None,
+        }
+    }
+
+    pub fn next_token(&mut self) -> Token {
+        self.skip_whitespace_and_comments();
+
+        let Some(c) = self.current else {
+            return Token::Eof;
         };
 
-        if token != Token::Eof {
+        // Try single-character tokens first
+        if let Some(token) = self.scan_single_char_token(c) {
             self.advance();
+            return token;
         }
 
-        token
+        // Try operators (may be multi-character)
+        if let Some(token) = self.scan_operator(c) {
+            self.advance();
+            return token;
+        }
+
+        // String literals
+        if c == '"' {
+            let token = match self.read_string() {
+                Ok(s) => Token::String(s),
+                Err(e) => {
+                    eprintln!("Lexer error on line {}: {}", self.line, e);
+                    // Skip to next quote or end
+                    while let Some(ch) = self.current {
+                        if ch == '"' || ch == '\n' {
+                            break;
+                        }
+                        self.advance();
+                    }
+                    Token::String(String::new())
+                }
+            };
+            self.advance();
+            return token;
+        }
+
+        // Identifiers and keywords
+        if c.is_alphabetic() || c == '_' {
+            let token = self.keyword_or_identifier();
+            self.advance();
+            return token;
+        }
+
+        // Numbers (decimal, hex, binary)
+        if c.is_ascii_digit() {
+            let token = match self.read_number() {
+                Ok(num) => Token::Integer(num),
+                Err(e) => {
+                    eprintln!("Lexer error on line {}: {}", self.line, e);
+                    // Skip invalid number
+                    while let Some(&ch) = self.peek() {
+                        if !ch.is_alphanumeric() {
+                            break;
+                        }
+                        self.advance();
+                    }
+                    Token::Integer(0)
+                }
+            };
+            self.advance();
+            return token;
+        }
+
+        // Unknown character - skip it
+        eprintln!(
+            "Lexer warning on line {}: Skipping unknown character '{}'",
+            self.line, c
+        );
+        self.advance();
+        self.next_token()
     }
 }
 
@@ -318,6 +580,41 @@ mod tests {
         assert_eq!(lexer.next_token(), Token::Eof);
     }
 
+    #[test]
+    fn test_hex_numbers() {
+        let input = "0xFF 0x10 0xDEADBEEF 0x0";
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(lexer.next_token(), Token::Integer(0xFF));
+        assert_eq!(lexer.next_token(), Token::Integer(0x10));
+        assert_eq!(lexer.next_token(), Token::Integer(0xDEADBEEF));
+        assert_eq!(lexer.next_token(), Token::Integer(0x0));
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
+    #[test]
+    fn test_binary_numbers() {
+        let input = "0b1010 0b0 0b11111111 0b1";
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(lexer.next_token(), Token::Integer(0b1010));
+        assert_eq!(lexer.next_token(), Token::Integer(0b0));
+        assert_eq!(lexer.next_token(), Token::Integer(0b11111111));
+        assert_eq!(lexer.next_token(), Token::Integer(0b1));
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
+    #[test]
+    fn test_mixed_number_formats() {
+        let input = "42 0xFF 0b1010";
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(lexer.next_token(), Token::Integer(42));
+        assert_eq!(lexer.next_token(), Token::Integer(255));
+        assert_eq!(lexer.next_token(), Token::Integer(10));
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
     #[test]
     fn test_operators() {
         let input = "= == ! != < <= > >=";
@@ -334,6 +631,19 @@ mod tests {
         assert_eq!(lexer.next_token(), Token::Eof);
     }
 
+    #[test]
+    fn test_string_with_escapes() {
+        let input = r#""hello\nworld" "tab\there""#;
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(
+            lexer.next_token(),
+            Token::String("hello\nworld".to_string())
+        );
+        assert_eq!(lexer.next_token(), Token::String("tab\there".to_string()));
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
     #[test]
     fn test_example_syntax() {
         let input = r#"
@@ -349,25 +659,108 @@ mod tests {
 
         let mut lexer = Lexer::new(input);
 
-        // Skip whitespace and newlines
-        while let Some(c) = lexer.current {
-            if !c.is_whitespace() {
-                break;
-            }
-            lexer.advance();
-        }
-
         // Test the first few tokens
         assert_eq!(lexer.next_token(), Token::Identifier("main".to_string()));
         assert_eq!(lexer.next_token(), Token::Colon);
         assert_eq!(lexer.next_token(), Token::Identifier("Func".to_string()));
         assert_eq!(lexer.next_token(), Token::Assign);
-        // assert_eq!(lexer.next_token(), Token::Pipe);
         assert_eq!(lexer.next_token(), Token::Identifier("x".to_string()));
         assert_eq!(lexer.next_token(), Token::Colon);
         assert_eq!(lexer.next_token(), Token::Identifier("U32".to_string()));
         assert_eq!(lexer.next_token(), Token::Comma);
+    }
 
-        // The rest of the tokens would be tested similarly
+    #[test]
+    fn test_line_comments() {
+        let input = r#"
+        let x = 5; // this is a comment
+        // this is another comment
+        let y = 10;
+        "#;
+
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(lexer.next_token(), Token::Let);
+        assert_eq!(lexer.next_token(), Token::Identifier("x".to_string()));
+        assert_eq!(lexer.next_token(), Token::Assign);
+        assert_eq!(lexer.next_token(), Token::Integer(5));
+        assert_eq!(lexer.next_token(), Token::Semicolon);
+        // Comment should be skipped
+        assert_eq!(lexer.next_token(), Token::Let);
+        assert_eq!(lexer.next_token(), Token::Identifier("y".to_string()));
+        assert_eq!(lexer.next_token(), Token::Assign);
+        assert_eq!(lexer.next_token(), Token::Integer(10));
+        assert_eq!(lexer.next_token(), Token::Semicolon);
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
+    #[test]
+    fn test_block_comments() {
+        let input = r#"
+        let x = 5; /* this is a
+        multiline block comment */
+        let y = 10;
+        "#;
+
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(lexer.next_token(), Token::Let);
+        assert_eq!(lexer.next_token(), Token::Identifier("x".to_string()));
+        assert_eq!(lexer.next_token(), Token::Assign);
+        assert_eq!(lexer.next_token(), Token::Integer(5));
+        assert_eq!(lexer.next_token(), Token::Semicolon);
+        // Block comment should be skipped
+        assert_eq!(lexer.next_token(), Token::Let);
+        assert_eq!(lexer.next_token(), Token::Identifier("y".to_string()));
+        assert_eq!(lexer.next_token(), Token::Assign);
+        assert_eq!(lexer.next_token(), Token::Integer(10));
+        assert_eq!(lexer.next_token(), Token::Semicolon);
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
+    #[test]
+    fn test_division_operator() {
+        let input = "x / y";
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(lexer.next_token(), Token::Identifier("x".to_string()));
+        assert_eq!(lexer.next_token(), Token::Slash);
+        assert_eq!(lexer.next_token(), Token::Identifier("y".to_string()));
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
+    #[test]
+    fn test_mixed_comments_and_operators() {
+        let input = r#"
+        x / y // division
+        /* block comment */ z = 10
+        a /= b // this won't work yet
+        "#;
+
+        let mut lexer = Lexer::new(input);
+
+        assert_eq!(lexer.next_token(), Token::Identifier("x".to_string()));
+        assert_eq!(lexer.next_token(), Token::Slash);
+        assert_eq!(lexer.next_token(), Token::Identifier("y".to_string()));
+        assert_eq!(lexer.next_token(), Token::Identifier("z".to_string()));
+        assert_eq!(lexer.next_token(), Token::Assign);
+        assert_eq!(lexer.next_token(), Token::Integer(10));
+        assert_eq!(lexer.next_token(), Token::Identifier("a".to_string()));
+        assert_eq!(lexer.next_token(), Token::Slash);
+        assert_eq!(lexer.next_token(), Token::Assign);
+        assert_eq!(lexer.next_token(), Token::Identifier("b".to_string()));
+        assert_eq!(lexer.next_token(), Token::Eof);
+    }
+
+    #[test]
+    fn test_nested_block_comment_attempt() {
+        // Note: This lexer doesn't support nested block comments
+        let input = "/* outer /* inner */ still in comment? */ x";
+        let mut lexer = Lexer::new(input);
+
+        // The comment ends at the first */
+        assert_eq!(lexer.next_token(), Token::Identifier("still".to_string()));
+        assert_eq!(lexer.next_token(), Token::Identifier("in".to_string()));
+        assert_eq!(lexer.next_token(), Token::Identifier("comment".to_string()));
     }
 }

compiler/src/parser.rs

@@ -247,6 +247,45 @@ impl Parser {
             return ParseResult::Accept(Statement::Continue);
         }
 
+        // handle writes to pointers!
+        if expect_tt!(self.peek_next()?, Star).accepted() {
+            self.next()?;
+
+            let left = if expect_tt!(self.peek_next()?, Identifier).accepted() {
+                let identifier = self.parse_identifier()?;
+
+                Expression::Variable {
+                    name: identifier,
+                    expr_type: None,
+                }
+            } else if expect_tt!(self.peek_next()?, LeftParen).accepted() {
+                self.next()?;
+
+                let expr = self.parse_expression()?;
+
+                let _ = expect_tt!(self.next()?, RightParen).accepted();
+
+                expr
+            } else {
+                return ParseResult::Reject(CompilerError::UnexpectedToken(
+                    self.peek_next()?,
+                ));
+            };
+
+            let _ = expect_tt!(self.next()?, Assign)?;
+
+            let right = self.parse_expression()?;
+
+            // expect semicolon
+            expect_tt!(self.next()?, Semicolon)?;
+
+            // return result
+            return ParseResult::Accept(Statement::PtrWrite {
+                ptr: left,
+                value: right,
+            });
+        }
+
         // handle let statements (declarations)
         if expect_tt!(self.peek_next()?, Let).accepted() {
             self.next();
@@ -573,6 +612,10 @@ pub enum Statement {
         varname: String,
         value: Expression,
     },
+    PtrWrite {
+        ptr: Expression,
+        value: Expression,
+    },
     Expression {
         expr: Expression,
     },