Function parseUnaryExpression

scripts/libs/esprima.js:2824–2861

()

    // 11.4 Unary Operators

    function parseUnaryExpression() {
        var token, expr, startToken;

        if (lookahead.type !== Token.Punctuator && lookahead.type !== Token.Keyword) {
            expr = parsePostfixExpression();
        } else if (match('++') || match('--')) {
            startToken = lookahead;
            token = lex();
            expr = parseUnaryExpression();
            // 11.4.4, 11.4.5
            if (strict && expr.type === Syntax.Identifier && isRestrictedWord(expr.name)) {
                tolerateError(Messages.StrictLHSPrefix);
            }

            if (!isLeftHandSide(expr)) {
                tolerateError(Messages.InvalidLHSInAssignment);
            }

            expr = new WrappingNode(startToken).finishUnaryExpression(token.value, expr);
        } else if (match('+') || match('-') || match('~') || match('!')) {
            startToken = lookahead;
            token = lex();
            expr = parseUnaryExpression();
            expr = new WrappingNode(startToken).finishUnaryExpression(token.value, expr);
        } else if (matchKeyword('delete') || matchKeyword('void') || matchKeyword('typeof')) {
            startToken = lookahead;
            token = lex();
            expr = parseUnaryExpression();
            expr = new WrappingNode(startToken).finishUnaryExpression(token.value, expr);
            if (strict && expr.operator === 'delete' && expr.argument.type === Syntax.Identifier) {
                tolerateError(Messages.StrictDelete);
            }
        } else {
            expr = parsePostfixExpression();
        }

        return expr;
    }

    function binaryPrecedence(token, allowIn) {
        var prec = 0;