Fix dot notations precedence; Add some miscellaneous expansions

dust-lang/src/abstract_tree.rs

@@ -62,10 +62,6 @@ pub enum Statement {
         value_arguments: Option<Vec<Node<Statement>>>,
     },
 
-    // Property access expression
-    // TODO: This should be a binary operation
-    PropertyAccess(Box<Node<Statement>>, Box<Node<Statement>>),
-
     // Loops
     While {
         condition: Box<Node<Statement>>,
@@ -113,7 +109,11 @@ impl Statement {
     pub fn expected_type(&self, context: &Context) -> Option<Type> {
         match self {
             Statement::Block(nodes) => nodes.last().unwrap().inner.expected_type(context),
-            Statement::BinaryOperation { left, operator, .. } => match operator.inner {
+            Statement::BinaryOperation {
+                left,
+                operator,
+                right,
+            } => match operator.inner {
                 BinaryOperator::Add
                 | BinaryOperator::Divide
                 | BinaryOperator::Modulo
@@ -129,6 +129,21 @@ impl Statement {
                 | BinaryOperator::Or => Some(Type::Boolean),
 
                 BinaryOperator::Assign | BinaryOperator::AddAssign => None,
+
+                BinaryOperator::FieldAccess => {
+                    let left_type = left.inner.expected_type(context)?;
+
+                    if let Type::Map(properties) = left_type {
+                        let key = match &right.inner {
+                            Statement::Identifier(identifier) => identifier,
+                            _ => return None,
+                        };
+
+                        properties.get(key).cloned()
+                    } else {
+                        None
+                    }
+                }
             },
             Statement::BuiltInFunctionCall { function, .. } => function.expected_return_type(),
             Statement::Constant(value) => Some(value.r#type(context)),
@@ -157,7 +172,6 @@ impl Statement {
                 Some(Type::Map(types))
             }
             Statement::Nil(_) => None,
-            Statement::PropertyAccess(_, _) => None,
             Statement::UnaryOperation { operator, operand } => match operator.inner {
                 UnaryOperator::Negate => Some(operand.inner.expected_type(context)?),
                 UnaryOperator::Not => Some(Type::Boolean),
@@ -202,7 +216,11 @@ impl Display for Statement {
                 operator,
                 right,
             } => {
-                write!(f, "{left} {operator} {right}")
+                if let BinaryOperator::FieldAccess = operator.inner {
+                    write!(f, "{left}{operator}{right}")
+                } else {
+                    write!(f, "{left} {operator} {right}")
+                }
             }
             Statement::BuiltInFunctionCall {
                 function,
@@ -340,7 +358,6 @@ impl Display for Statement {
                 write!(f, "}}")
             }
             Statement::Nil(node) => write!(f, "{node};"),
-            Statement::PropertyAccess(left, right) => write!(f, "{left}.{right}"),
             Statement::UnaryOperation { operator, operand } => {
                 write!(f, "{operator}{operand}")
             }
@@ -353,6 +370,8 @@ impl Display for Statement {
 
 #[derive(Debug, Clone, Eq, PartialEq, PartialOrd, Ord, Serialize, Deserialize)]
 pub enum BinaryOperator {
+    FieldAccess,
+
     // Math
     Add,
     Divide,
@@ -385,6 +404,7 @@ impl Display for BinaryOperator {
             BinaryOperator::And => write!(f, "&&"),
             BinaryOperator::Divide => write!(f, "/"),
             BinaryOperator::Equal => write!(f, "=="),
+            BinaryOperator::FieldAccess => write!(f, "."),
             BinaryOperator::Greater => write!(f, ">"),
             BinaryOperator::GreaterOrEqual => write!(f, ">="),
             BinaryOperator::Less => write!(f, "<"),

dust-lang/src/analyzer.rs

@@ -96,6 +96,44 @@ impl<'a> Analyzer<'a> {
                     }
                 }
 
+                if let BinaryOperator::FieldAccess = operator.inner {
+                    self.analyze_statement(left)?;
+
+                    if let Statement::Identifier(_) = right.inner {
+                        // Do not expect a value for property accessors
+                    } else {
+                        self.analyze_statement(right)?;
+                    }
+
+                    if let Some(Type::List { .. }) = left.inner.expected_type(self.context) {
+                        let right_type = right.inner.expected_type(self.context);
+
+                        if let Some(Type::Integer) = right_type {
+                            // Allow indexing lists with integers
+                        } else if let Some(Type::Range) = right_type {
+                            // Allow indexing lists with ranges
+                        } else {
+                            return Err(AnalyzerError::ExpectedIntegerOrRange {
+                                actual: right.as_ref().clone(),
+                            });
+                        }
+                    }
+
+                    if let Some(Type::Map { .. }) = left.inner.expected_type(self.context) {
+                        if let Some(Type::String) = right.inner.expected_type(self.context) {
+                            // Allow indexing maps with strings
+                        } else if let Statement::Identifier(_) = right.inner {
+                            // Allow indexing maps with identifiers
+                        } else {
+                            return Err(AnalyzerError::ExpectedIdentifierOrString {
+                                actual: right.as_ref().clone(),
+                            });
+                        }
+                    }
+
+                    return Ok(());
+                }
+
                 self.analyze_statement(left)?;
                 self.analyze_statement(right)?;
 
@@ -324,41 +362,6 @@ impl<'a> Analyzer<'a> {
             Statement::Nil(node) => {
                 self.analyze_statement(node)?;
             }
-            Statement::PropertyAccess(left, right) => {
-                self.analyze_statement(left)?;
-
-                if let Statement::Identifier(_) = right.inner {
-                    // Do not expect a value for property accessors
-                } else {
-                    self.analyze_statement(right)?;
-                }
-
-                if let Some(Type::List { .. }) = left.inner.expected_type(self.context) {
-                    let right_type = right.inner.expected_type(self.context);
-
-                    if let Some(Type::Integer) = right_type {
-                        // Allow indexing lists with integers
-                    } else if let Some(Type::Range) = right_type {
-                        // Allow indexing lists with ranges
-                    } else {
-                        return Err(AnalyzerError::ExpectedIntegerOrRange {
-                            actual: right.as_ref().clone(),
-                        });
-                    }
-                }
-
-                if let Some(Type::Map { .. }) = left.inner.expected_type(self.context) {
-                    if let Some(Type::String) = right.inner.expected_type(self.context) {
-                        // Allow indexing maps with strings
-                    } else if let Statement::Identifier(_) = right.inner {
-                        // Allow indexing maps with identifiers
-                    } else {
-                        return Err(AnalyzerError::ExpectedIdentifierOrString {
-                            actual: right.as_ref().clone(),
-                        });
-                    }
-                }
-            }
             Statement::UnaryOperation { operator, operand } => {
                 self.analyze_statement(operand)?;
 

dust-lang/src/lexer.rs

@@ -264,6 +264,11 @@ impl Lexer {
 
                     (Token::Bang, (self.position - 1, self.position))
                 }
+                ':' => {
+                    self.position += 1;
+
+                    (Token::Colon, (self.position - 1, self.position))
+                }
                 _ => {
                     self.position += 1;
 
@@ -408,13 +413,17 @@ impl Lexer {
         let token = match string {
             "Infinity" => Token::Float("Infinity"),
             "NaN" => Token::Float("NaN"),
+            "bool" => Token::Bool,
             "else" => Token::Else,
             "false" => Token::Boolean("false"),
+            "float" => Token::FloatKeyword,
             "if" => Token::If,
+            "int" => Token::Int,
             "is_even" => Token::IsEven,
             "is_odd" => Token::IsOdd,
             "length" => Token::Length,
             "read_line" => Token::ReadLine,
+            "struct" => Token::Struct,
             "to_string" => Token::ToString,
             "true" => Token::Boolean("true"),
             "while" => Token::While,

dust-lang/src/parser.rs

@@ -604,6 +604,8 @@ impl<'src> Parser<'src> {
             };
 
         if let Token::Dot = &self.current.0 {
+            let operator_position = self.current.1;
+
             self.next_token()?;
 
             let right = self.parse_statement(operator_precedence)?;
@@ -658,7 +660,11 @@ impl<'src> Parser<'src> {
             }
 
             return Ok(Node::new(
-                Statement::PropertyAccess(Box::new(left), Box::new(right)),
+                Statement::BinaryOperation {
+                    left: Box::new(left),
+                    operator: Node::new(BinaryOperator::FieldAccess, operator_position),
+                    right: Box::new(right),
+                },
                 (left_start, right_end),
             ));
         }
@@ -852,47 +858,48 @@ mod tests {
         assert_eq!(
             parse(input),
             Ok(AbstractSyntaxTree {
-                nodes: [Node {
+                nodes: [Node::new(
-                    inner: Statement::PropertyAccess(
+                    Statement::BinaryOperation {
-                        Box::new(Node {
+                        left: Box::new(Node::new(
-                            inner: Statement::Map(vec![(
+                            Statement::BinaryOperation {
-                                Node {
+                                left: Box::new(Node::new(
-                                    inner: Statement::Identifier(Identifier::new("x")),
+                                    Statement::Map(vec![(
-                                    position: (2, 3)
+                                        Node::new(
-                                },
+                                            Statement::Identifier(Identifier::new("x")),
-                                Node {
+                                            (2, 3)
-                                    inner: Statement::Map(vec![(
+                                        ),
-                                        Node {
+                                        Node::new(
-                                            inner: Statement::Identifier(Identifier::new("y")),
+                                            Statement::Map(vec![(
-                                            position: (8, 9)
+                                                Node::new(
-                                        },
+                                                    Statement::Identifier(Identifier::new("y")),
-                                        Node {
+                                                    (8, 9)
-                                            inner: Statement::Constant(Value::integer(42)),
+                                                ),
-                                            position: (12, 14)
+                                                Node::new(
-                                        }
+                                                    Statement::Constant(Value::integer(42)),
+                                                    (12, 14)
+                                                )
+                                            )]),
+                                            (6, 16)
+                                        )
                                     )]),
-                                    position: (6, 16)
+                                    (0, 18)
-                                }
+                                )),
-                            )]),
+                                operator: Node::new(BinaryOperator::FieldAccess, (18, 19)),
-                            position: (0, 18)
+                                right: Box::new(Node::new(
-                        }),
+                                    Statement::Identifier(Identifier::new("x")),
-                        Box::new(Node {
+                                    (19, 20)
-                            inner: Statement::PropertyAccess(
+                                ))
-                                Box::new(Node {
+                            },
-                                    inner: Statement::Identifier(Identifier::new("x")),
+                            (0, 20)
-                                    position: (19, 20)
+                        )),
-                                }),
+                        operator: Node::new(BinaryOperator::FieldAccess, (20, 21)),
-                                Box::new(Node {
+                        right: Box::new(Node::new(
-                                    inner: Statement::Identifier(Identifier::new("y")),
+                            Statement::Identifier(Identifier::new("y")),
-
+                            (21, 22)
-                                    position: (21, 22)
+                        ))
-                                })
+                    },
-                            ),
+                    (0, 22)
-                            position: (19, 22)
+                )]
-                        })
-                    ),
-                    position: (0, 22)
-                }]
                 .into()
             })
         )
@@ -1444,7 +1451,7 @@ mod tests {
     }
 
     #[test]
-    fn map_with_two_properties() {
+    fn map_with_two_fields() {
         let input = "{ x = 42, y = 'foobar' }";
 
         assert_eq!(
@@ -1469,8 +1476,8 @@ mod tests {
     }
 
     #[test]
-    fn map_with_one_property() {
+    fn map_with_one_field() {
-        let input = "{ x = 42, }";
+        let input = "{ x = 42 }";
 
         assert_eq!(
             parse(input),
@@ -1480,7 +1487,7 @@ mod tests {
                         Node::new(Statement::Identifier(Identifier::new("x")), (2, 3)),
                         Node::new(Statement::Constant(Value::integer(42)), (6, 8))
                     )]),
-                    (0, 11)
+                    (0, 10)
                 )]
                 .into()
             })
@@ -1732,8 +1739,8 @@ mod tests {
             parse(input),
             Ok(AbstractSyntaxTree {
                 nodes: [Node::new(
-                    Statement::PropertyAccess(
+                    Statement::BinaryOperation {
-                        Box::new(Node::new(
+                        left: Box::new(Node::new(
                             Statement::List(vec![
                                 Node::new(Statement::Constant(Value::integer(1)), (1, 2)),
                                 Node::new(Statement::Constant(Value::integer(2)), (4, 5)),
@@ -1741,8 +1748,12 @@ mod tests {
                             ]),
                             (0, 9)
                         )),
-                        Box::new(Node::new(Statement::Constant(Value::integer(0)), (10, 11))),
+                        operator: Node::new(BinaryOperator::FieldAccess, (9, 10)),
-                    ),
+                        right: Box::new(Node::new(
+                            Statement::Constant(Value::integer(0)),
+                            (10, 11)
+                        )),
+                    },
                     (0, 11),
                 )]
                 .into()
@@ -1758,16 +1769,17 @@ mod tests {
             parse(input),
             Ok(AbstractSyntaxTree {
                 nodes: [Node::new(
-                    Statement::PropertyAccess(
+                    Statement::BinaryOperation {
-                        Box::new(Node::new(
+                        left: Box::new(Node::new(
                             Statement::Identifier(Identifier::new("a")),
                             (0, 1)
                         )),
-                        Box::new(Node::new(
+                        operator: Node::new(BinaryOperator::FieldAccess, (1, 2)),
+                        right: Box::new(Node::new(
                             Statement::Identifier(Identifier::new("b")),
                             (2, 3)
                         )),
-                    ),
+                    },
                     (0, 3),
                 )]
                 .into()

dust-lang/src/token.rs

@@ -17,18 +17,24 @@ pub enum Token<'src> {
     String(&'src str),
 
     // Keywords
+    Bool,
     Else,
+    FloatKeyword,
     If,
+    Int,
     IsEven,
     IsOdd,
     Length,
     ReadLine,
+    Str,
+    Struct,
     ToString,
     While,
     WriteLine,
 
     // Symbols
     Bang,
+    Colon,
     Comma,
     Dot,
     DoubleAmpersand,
@@ -59,7 +65,9 @@ impl<'src> Token<'src> {
     pub fn to_owned(&self) -> TokenOwned {
         match self {
             Token::Bang => TokenOwned::Bang,
+            Token::Bool => TokenOwned::Bool,
             Token::Boolean(boolean) => TokenOwned::Boolean(boolean.to_string()),
+            Token::Colon => TokenOwned::Colon,
             Token::Comma => TokenOwned::Comma,
             Token::Dot => TokenOwned::Dot,
             Token::DoubleAmpersand => TokenOwned::DoubleAmpersand,
@@ -70,10 +78,12 @@ impl<'src> Token<'src> {
             Token::Eof => TokenOwned::Eof,
             Token::Equal => TokenOwned::Equal,
             Token::Float(float) => TokenOwned::Float(float.to_string()),
+            Token::FloatKeyword => TokenOwned::FloatKeyword,
             Token::Greater => TokenOwned::Greater,
             Token::GreaterEqual => TokenOwned::GreaterOrEqual,
             Token::Identifier(text) => TokenOwned::Identifier(text.to_string()),
             Token::If => TokenOwned::If,
+            Token::Int => TokenOwned::Int,
             Token::Integer(integer) => TokenOwned::Integer(integer.to_string()),
             Token::IsEven => TokenOwned::IsEven,
             Token::IsOdd => TokenOwned::IsOdd,
@@ -95,6 +105,8 @@ impl<'src> Token<'src> {
             Token::Star => TokenOwned::Star,
             Token::Slash => TokenOwned::Slash,
             Token::String(text) => TokenOwned::String(text.to_string()),
+            Token::Str => TokenOwned::Str,
+            Token::Struct => TokenOwned::Struct,
             Token::ToString => TokenOwned::ToString,
             Token::While => TokenOwned::While,
             Token::WriteLine => TokenOwned::WriteLine,
@@ -104,11 +116,14 @@ impl<'src> Token<'src> {
     pub fn as_str(&self) -> &str {
         match self {
             Token::Boolean(boolean_text) => boolean_text,
+            Token::Float(float_text) => float_text,
             Token::Identifier(text) => text,
             Token::Integer(integer_text) => integer_text,
             Token::String(text) => text,
 
             Token::Bang => "!",
+            Token::Bool => "bool",
+            Token::Colon => ":",
             Token::Comma => ",",
             Token::Dot => ".",
             Token::DoubleAmpersand => "&&",
@@ -118,10 +133,11 @@ impl<'src> Token<'src> {
             Token::Else => "else",
             Token::Eof => "EOF",
             Token::Equal => "=",
-            Token::Float(_) => "float",
+            Token::FloatKeyword => "float",
             Token::Greater => ">",
             Token::GreaterEqual => ">=",
             Token::If => "if",
+            Token::Int => "int",
             Token::IsEven => "is_even",
             Token::IsOdd => "is_odd",
             Token::LeftCurlyBrace => "{",
@@ -141,6 +157,8 @@ impl<'src> Token<'src> {
             Token::Semicolon => ";",
             Token::Star => "*",
             Token::Slash => "/",
+            Token::Str => "str",
+            Token::Struct => "struct",
             Token::ToString => "to_string",
             Token::While => "while",
             Token::WriteLine => "write_line",
@@ -150,7 +168,9 @@ impl<'src> Token<'src> {
     pub fn kind(&self) -> TokenKind {
         match self {
             Token::Bang => TokenKind::Bang,
+            Token::Bool => TokenKind::Bool,
             Token::Boolean(_) => TokenKind::Boolean,
+            Token::Colon => TokenKind::Colon,
             Token::Comma => TokenKind::Comma,
             Token::Dot => TokenKind::Dot,
             Token::DoubleAmpersand => TokenKind::DoubleAmpersand,
@@ -161,10 +181,12 @@ impl<'src> Token<'src> {
             Token::Eof => TokenKind::Eof,
             Token::Equal => TokenKind::Equal,
             Token::Float(_) => TokenKind::Float,
+            Token::FloatKeyword => TokenKind::FloatKeyword,
             Token::Greater => TokenKind::Greater,
             Token::GreaterEqual => TokenKind::GreaterOrEqual,
             Token::Identifier(_) => TokenKind::Identifier,
             Token::If => TokenKind::If,
+            Token::Int => TokenKind::Int,
             Token::Integer(_) => TokenKind::Integer,
             Token::IsEven => TokenKind::IsEven,
             Token::IsOdd => TokenKind::IsOdd,
@@ -185,7 +207,9 @@ impl<'src> Token<'src> {
             Token::Semicolon => TokenKind::Semicolon,
             Token::Star => TokenKind::Star,
             Token::Slash => TokenKind::Slash,
+            Token::Str => TokenKind::Str,
             Token::String(_) => TokenKind::String,
+            Token::Struct => TokenKind::Struct,
             Token::ToString => TokenKind::ToString,
             Token::While => TokenKind::While,
             Token::WriteLine => TokenKind::WriteLine,
@@ -301,18 +325,23 @@ pub enum TokenOwned {
     String(String),
 
     // Keywords
+    Bool,
     Else,
+    FloatKeyword,
     If,
+    Int,
     IsEven,
     IsOdd,
     Length,
     ReadLine,
+    Str,
     ToString,
     While,
     WriteLine,
 
     // Symbols
     Bang,
+    Colon,
     Comma,
     Dot,
     DoubleAmpersand,
@@ -336,6 +365,7 @@ pub enum TokenOwned {
     RightSquareBrace,
     Semicolon,
     Star,
+    Struct,
     Slash,
 }
 
@@ -343,7 +373,9 @@ impl Display for TokenOwned {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         match self {
             TokenOwned::Bang => Token::Bang.fmt(f),
+            TokenOwned::Bool => write!(f, "bool"),
             TokenOwned::Boolean(boolean) => write!(f, "{boolean}"),
+            TokenOwned::Colon => Token::Colon.fmt(f),
             TokenOwned::Comma => Token::Comma.fmt(f),
             TokenOwned::Dot => Token::Dot.fmt(f),
             TokenOwned::DoubleAmpersand => Token::DoubleAmpersand.fmt(f),
@@ -354,10 +386,12 @@ impl Display for TokenOwned {
             TokenOwned::Eof => Token::Eof.fmt(f),
             TokenOwned::Equal => Token::Equal.fmt(f),
             TokenOwned::Float(float) => write!(f, "{float}"),
+            TokenOwned::FloatKeyword => write!(f, "float"),
             TokenOwned::Greater => Token::Greater.fmt(f),
             TokenOwned::GreaterOrEqual => Token::GreaterEqual.fmt(f),
             TokenOwned::Identifier(text) => write!(f, "{text}"),
             TokenOwned::If => Token::If.fmt(f),
+            TokenOwned::Int => write!(f, "int"),
             TokenOwned::Integer(integer) => write!(f, "{integer}"),
             TokenOwned::IsEven => Token::IsEven.fmt(f),
             TokenOwned::IsOdd => Token::IsOdd.fmt(f),
@@ -378,7 +412,9 @@ impl Display for TokenOwned {
             TokenOwned::Semicolon => Token::Semicolon.fmt(f),
             TokenOwned::Star => Token::Star.fmt(f),
             TokenOwned::Slash => Token::Slash.fmt(f),
+            TokenOwned::Str => write!(f, "str"),
             TokenOwned::String(string) => write!(f, "{string}"),
+            TokenOwned::Struct => Token::Struct.fmt(f),
             TokenOwned::ToString => Token::ToString.fmt(f),
             TokenOwned::While => Token::While.fmt(f),
             TokenOwned::WriteLine => Token::WriteLine.fmt(f),
@@ -400,18 +436,23 @@ pub enum TokenKind {
     String,
 
     // Keywords
+    Bool,
     Else,
+    FloatKeyword,
     If,
+    Int,
     IsEven,
     IsOdd,
     Length,
     ReadLine,
+    Str,
     ToString,
     While,
     WriteLine,
 
     // Symbols
     Bang,
+    Colon,
     Comma,
     Dot,
     DoubleAmpersand,
@@ -435,6 +476,7 @@ pub enum TokenKind {
     RightSquareBrace,
     Semicolon,
     Star,
+    Struct,
     Slash,
 }
 
@@ -442,7 +484,9 @@ impl Display for TokenKind {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
         match self {
             TokenKind::Bang => Token::Bang.fmt(f),
-            TokenKind::Boolean => write!(f, "boolean"),
+            TokenKind::Bool => Token::Bool.fmt(f),
+            TokenKind::Boolean => write!(f, "boolean value"),
+            TokenKind::Colon => Token::Colon.fmt(f),
             TokenKind::Comma => Token::Comma.fmt(f),
             TokenKind::Dot => Token::Dot.fmt(f),
             TokenKind::DoubleAmpersand => Token::DoubleAmpersand.fmt(f),
@@ -452,12 +496,14 @@ impl Display for TokenKind {
             TokenKind::Else => Token::Else.fmt(f),
             TokenKind::Eof => Token::Eof.fmt(f),
             TokenKind::Equal => Token::Equal.fmt(f),
-            TokenKind::Float => write!(f, "float"),
+            TokenKind::Float => write!(f, "float value"),
+            TokenKind::FloatKeyword => Token::FloatKeyword.fmt(f),
             TokenKind::Greater => Token::Greater.fmt(f),
             TokenKind::GreaterOrEqual => Token::GreaterEqual.fmt(f),
             TokenKind::Identifier => write!(f, "identifier"),
             TokenKind::If => Token::If.fmt(f),
-            TokenKind::Integer => write!(f, "integer"),
+            TokenKind::Int => Token::Int.fmt(f),
+            TokenKind::Integer => write!(f, "integer value"),
             TokenKind::IsEven => Token::IsEven.fmt(f),
             TokenKind::IsOdd => Token::IsOdd.fmt(f),
             TokenKind::LeftCurlyBrace => Token::LeftCurlyBrace.fmt(f),
@@ -476,11 +522,85 @@ impl Display for TokenKind {
             TokenKind::RightSquareBrace => Token::RightSquareBrace.fmt(f),
             TokenKind::Semicolon => Token::Semicolon.fmt(f),
             TokenKind::Star => Token::Star.fmt(f),
+            TokenKind::Str => write!(f, "str"),
             TokenKind::Slash => Token::Slash.fmt(f),
-            TokenKind::String => write!(f, "string"),
+            TokenKind::String => write!(f, "string value"),
+            TokenKind::Struct => Token::Struct.fmt(f),
             TokenKind::ToString => Token::ToString.fmt(f),
             TokenKind::While => Token::While.fmt(f),
             TokenKind::WriteLine => Token::WriteLine.fmt(f),
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    fn all_tokens<'src>() -> [Token<'src>; 42] {
+        [
+            Token::Bang,
+            Token::Boolean("true"),
+            Token::Colon,
+            Token::Comma,
+            Token::Dot,
+            Token::DoubleAmpersand,
+            Token::DoubleDot,
+            Token::DoubleEqual,
+            Token::DoublePipe,
+            Token::Else,
+            Token::Eof,
+            Token::Equal,
+            Token::Float("42.0"),
+            Token::Greater,
+            Token::GreaterEqual,
+            Token::Identifier("foobar"),
+            Token::If,
+            Token::Integer("42"),
+            Token::IsEven,
+            Token::IsOdd,
+            Token::LeftCurlyBrace,
+            Token::LeftParenthesis,
+            Token::LeftSquareBrace,
+            Token::Length,
+            Token::Less,
+            Token::LessEqual,
+            Token::Minus,
+            Token::Percent,
+            Token::Plus,
+            Token::PlusEqual,
+            Token::ReadLine,
+            Token::RightCurlyBrace,
+            Token::RightParenthesis,
+            Token::RightSquareBrace,
+            Token::Semicolon,
+            Token::Star,
+            Token::Slash,
+            Token::String("foobar"),
+            Token::Struct,
+            Token::ToString,
+            Token::While,
+            Token::WriteLine,
+        ]
+    }
+
+    #[test]
+    fn token_displays() {
+        for token in all_tokens().iter() {
+            let display = token.to_string();
+
+            assert_eq!(display, token.to_owned().to_string());
+
+            if let Token::Boolean(_)
+            | Token::Float(_)
+            | Token::Identifier(_)
+            | Token::Integer(_)
+            | Token::String(_) = token
+            {
+                continue;
+            } else {
+                assert_eq!(display, token.kind().to_string());
+            }
+        }
+    }
+}

dust-lang/src/type.rs

@@ -31,6 +31,7 @@ pub struct TypeConflict {
 pub enum Type {
     Any,
     Boolean,
+    Defined(Identifier),
     Enum {
         name: Identifier,
         type_parameters: Option<Vec<Type>>,
@@ -216,6 +217,7 @@ impl Display for Type {
         match self {
             Type::Any => write!(f, "any"),
             Type::Boolean => write!(f, "bool"),
+            Type::Defined(identifier) => write!(f, "{identifier}"),
             Type::Enum { variants, .. } => {
                 write!(f, "enum ")?;
 

dust-lang/src/value.rs

@@ -348,6 +348,7 @@ impl Display for Value {
             }
             ValueInner::Range(range) => write!(f, "{}..{}", range.start, range.end),
             ValueInner::String(string) => write!(f, "{string}"),
+            ValueInner::Struct(r#struct) => write!(f, "{struct}"),
         }
     }
 }
@@ -403,6 +404,7 @@ impl Serialize for Value {
                 tuple_ser.end()
             }
             ValueInner::String(string) => serializer.serialize_str(string),
+            ValueInner::Struct(r#struct) => r#struct.serialize(serializer),
         }
     }
 }
@@ -659,6 +661,7 @@ pub enum ValueInner {
     Map(BTreeMap<Identifier, Value>),
     Range(Range<i64>),
     String(String),
+    Struct(Struct),
 }
 
 impl ValueInner {
@@ -692,6 +695,7 @@ impl ValueInner {
             }
             ValueInner::Range(_) => Type::Range,
             ValueInner::String(_) => Type::String,
+            ValueInner::Struct(r#struct) => Type::Defined(r#struct.name().clone()),
         }
     }
 
@@ -747,6 +751,8 @@ impl Ord for ValueInner {
             (Range(_), _) => Ordering::Greater,
             (String(left), String(right)) => left.cmp(right),
             (String(_), _) => Ordering::Greater,
+            (Struct(left), Struct(right)) => left.cmp(right),
+            (Struct(_), _) => Ordering::Greater,
         }
     }
 }
@@ -832,6 +838,65 @@ impl Display for Function {
     }
 }
 
+#[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Serialize, Deserialize)]
+pub enum Struct {
+    Unit {
+        name: Identifier,
+    },
+    Tuple {
+        name: Identifier,
+        fields: Vec<Value>,
+    },
+    Fields {
+        name: Identifier,
+        fields: Vec<(Identifier, Value)>,
+    },
+}
+
+impl Struct {
+    pub fn name(&self) -> &Identifier {
+        match self {
+            Struct::Unit { name } => name,
+            Struct::Tuple { name, .. } => name,
+            Struct::Fields { name, .. } => name,
+        }
+    }
+}
+
+impl Display for Struct {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        match self {
+            Struct::Unit { name } => write!(f, "{}", name),
+            Struct::Tuple { name, fields } => {
+                write!(f, "{}(", name)?;
+
+                for (index, field) in fields.iter().enumerate() {
+                    if index > 0 {
+                        write!(f, ", ")?;
+                    }
+
+                    write!(f, "{}", field)?;
+                }
+
+                write!(f, ")")
+            }
+            Struct::Fields { name, fields } => {
+                write!(f, "{} {{", name)?;
+
+                for (index, (identifier, r#type)) in fields.iter().enumerate() {
+                    if index > 0 {
+                        write!(f, ", ")?;
+                    }
+
+                    write!(f, "{}: {}", identifier, r#type)?;
+                }
+
+                write!(f, "}}")
+            }
+        }
+    }
+}
+
 #[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 pub enum ValueError {
     CannotAdd(Value, Value),

dust-lang/src/vm.rs

@@ -137,6 +137,58 @@ impl Vm {
                     return Ok(None);
                 }
 
+                if let BinaryOperator::FieldAccess = operator.inner {
+                    let left_span = left.position;
+                    let left_value = if let Some(value) = self.run_statement(*left)? {
+                        value
+                    } else {
+                        return Err(VmError::ExpectedValue {
+                            position: left_span,
+                        });
+                    };
+                    let right_span = right.position;
+
+                    if let (Some(list), Statement::Constant(value)) =
+                        (left_value.as_list(), &right.inner)
+                    {
+                        if let Some(index) = value.as_integer() {
+                            let value = list.get(index as usize).cloned();
+
+                            return Ok(value);
+                        }
+
+                        if let Some(range) = value.as_range() {
+                            let range = range.start as usize..range.end as usize;
+
+                            if let Some(items) = list.get(range) {
+                                return Ok(Some(Value::list(items.to_vec())));
+                            }
+                        }
+                    }
+
+                    if let Some(map) = left_value.as_map() {
+                        if let Statement::Identifier(identifier) = right.inner {
+                            let value = map.get(&identifier).cloned();
+
+                            return Ok(value);
+                        }
+
+                        if let Some(value) = self.run_statement(*right)? {
+                            if let Some(string) = value.as_string() {
+                                let identifier = Identifier::new(string);
+
+                                let value = map.get(&identifier).cloned();
+
+                                return Ok(value);
+                            }
+                        }
+                    }
+
+                    return Err(VmError::ExpectedIdentifierIntegerOrRange {
+                        position: right_span,
+                    });
+                }
+
                 let left_position = left.position;
                 let left_value = if let Some(value) = self.run_statement(*left)? {
                     value
@@ -466,57 +518,6 @@ impl Vm {
 
                 Ok(None)
             }
-            Statement::PropertyAccess(left, right) => {
-                let left_span = left.position;
-                let left_value = if let Some(value) = self.run_statement(*left)? {
-                    value
-                } else {
-                    return Err(VmError::ExpectedValue {
-                        position: left_span,
-                    });
-                };
-                let right_span = right.position;
-
-                if let (Some(list), Statement::Constant(value)) =
-                    (left_value.as_list(), &right.inner)
-                {
-                    if let Some(index) = value.as_integer() {
-                        let value = list.get(index as usize).cloned();
-
-                        return Ok(value);
-                    }
-
-                    if let Some(range) = value.as_range() {
-                        let range = range.start as usize..range.end as usize;
-
-                        if let Some(items) = list.get(range) {
-                            return Ok(Some(Value::list(items.to_vec())));
-                        }
-                    }
-                }
-
-                if let Some(map) = left_value.as_map() {
-                    if let Statement::Identifier(identifier) = right.inner {
-                        let value = map.get(&identifier).cloned();
-
-                        return Ok(value);
-                    }
-
-                    if let Some(value) = self.run_statement(*right)? {
-                        if let Some(string) = value.as_string() {
-                            let identifier = Identifier::new(string);
-
-                            let value = map.get(&identifier).cloned();
-
-                            return Ok(value);
-                        }
-                    }
-                }
-
-                Err(VmError::ExpectedIdentifierIntegerOrRange {
-                    position: right_span,
-                })
-            }
             Statement::UnaryOperation { operator, operand } => {
                 let position = operand.position;
                 let value = if let Some(value) = self.run_statement(*operand)? {