Function lex

docs/app/js/sanddance-app.js:143997–144003

()

    return scanPunctuator();
}
function lex() {
    const token = lookahead;
    index = token.end;
    lookahead = advance();
    index = token.end;
    return token;
}
function peek() {
    const pos = index;
    lookahead = advance();