babalae/better-genshin-impact · error · InvalidOperationException

缺少右括号

Error message

缺少右括号

What it means

Thrown by ConditionEvaluator.ParsePrimary when a parenthesized sub-expression (opened with '(') is parsed but the closing ')' is not found at the expected position. This is a syntax error in the condition expression: an unbalanced '('. When called via Evaluate(), this is caught internally and Evaluate returns false.

Solutions

1. Count and balance all '(' and ')' in the condition expression.
2. The expression engine does not support implicit grouping — every '(' must have a matching ')'.
3. Simplify complex nested expressions and rebuild them incrementally, testing each part.
4. Use the Evaluate method in a dry-run with logging to identify the exact failure point.

Example fix

// before (unclosed paren)
"condition": "(q-ready() && low-hp"

// after
"condition": "(q-ready() && low-hp())"

// Quick balance check for parentheses in a condition expression
static bool AreParensBalanced(string expr)
{
    int depth = 0;
    foreach (var c in expr)
    {
        if (c == '(') depth++;
        if (c == ')') depth--;
        if (depth < 0) return false;
    }
    return depth == 0;
}

if (!AreParensBalanced(conditionExpr))
    Log.LogWarning("条件表达式括号不平衡: {Expr}", conditionExpr);

// Evaluate catches this internally (line 147-151) and returns false.
// No additional try-catch needed when using Evaluate.
// For safety, log the expression when Evaluate returns unexpected false:
var result = evaluator.Evaluate(expr, index, charName, actionName);
if (!result && /* expected true context */)
    Logger.LogWarning("条件求值返回false，可能表达式有语法错误: {Expr}", expr);

When it happens

Trigger: A condition expression with an unclosed parenthesis, e.g. `(q-ready() && low-hp` or `since(1 > 5`. The parser enters ParsePrimary expecting ')' after the inner expression, but finds a different token (End, or another operator/identifier).

Common situations: User writes a JSON strategy condition with a missing ')', or has unbalanced parentheses from manual editing. For example: `"condition": "(q-ready() && low-hp"` — the outer '(' is never closed.

Related errors

• 无法识别的字符：
• 函数 缺少右括号
• 意外的 token：
• 战斗脚本格式错误，指令括号无法配对
• 战斗脚本格式错误，指令括号不完整

AI-assisted analysis of babalae/better-genshin-impact@a7cb36712d (2026-08-13). Data as JSON: /api/errors/02964799fb52470b. Report an issue: GitHub.

Appendix: source

Thrown at BetterGenshinImpact/GameTask/AutoFight/Script/ConditionEvaluator.cs:341

        {
            var op = tokens[pos].Value; pos++;
            return new UnaryOpNode(op, ParseUnaryExpr(tokens, ref pos));
        }
        if (tokens[pos].Type == TokenType.Minus)
        {
            pos++;
            return new UnaryOpNode("-u", ParseUnaryExpr(tokens, ref pos));
        }
        return ParsePrimary(tokens, ref pos);
    }

    private static AstNode ParsePrimary(List<Token> tokens, ref int pos)
    {
        if (tokens[pos].Type == TokenType.LParen)
        {
            pos++;
            var node = ParseOrExpr(tokens, ref pos);
            if (tokens[pos].Type != TokenType.RParen) throw new InvalidOperationException("缺少右括号");
            pos++;
            return node;
        }

        if (tokens[pos].Type == TokenType.Identifier)
        {
            var name = tokens[pos].Value; pos++;
            if (tokens[pos].Type == TokenType.LParen)
            {
                pos++;
                var args = new List<AstNode>();
                if (tokens[pos].Type != TokenType.RParen)
                {
                    args.Add(ParseOrExpr(tokens, ref pos));
                    while (tokens[pos].Type == TokenType.Comma)
                    {
                        pos++;
                        args.Add(ParseOrExpr(tokens, ref pos));

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