// lexer/token.rs
#[derive(Debug, Clone, PartialEq)]
pub enum TokenKind {
    // 单字符
    LeftParen, RightParen,
    LeftBrace, RightBrace,
    LeftBracket, RightBracket,
    Comma, Semicolon, Dot,
    Colon,

    // 运算符
    Plus, Minus, Star, Slash,
    Bang,
    Equal,
    Greater, GreaterEqual,
    Less, LessEqual,
    EqualEqual, BangEqual,
    AndAnd, OrOr,

    // 字面量
    Identifier(String),
    Number(f64),
    String(String),

    // 关键字
    Let,
    Fn,
    If,
    Else,
    While,
    For,
    Break,
    Continue,
    Return,
    True,
    False,
    Nil,

    EOF,
}

#[derive(Debug, Clone)]
pub struct Token {
    pub kind: TokenKind,
    pub line: usize,
    pub column: usize,
}