alibaba/QLExpress

为什么自定义符号很多不支持 比如 ≠、≥、≤

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#414 opened on Dec 2, 2025

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help wanted

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Description

Caused by: com.alibaba.qlexpress4.exception.QLSyntaxException: [Error SYNTAX_ERROR: rule nextStatement failed predicate: {_input.LA(1) == Token.EOF || _input.LA(1) == QLexer.RBRACE}?] [Near: 1 ≠ 2] ^ [Line: 1, Column: 2] at com.alibaba.qlexpress4.exception.QLException.reportScannerErr(QLException.java:56) at com.alibaba.qlexpress4.aparser.QLErrorListener.syntaxError(QLErrorListener.java:28) at com.alibaba.qlexpress4.a4runtime.ProxyErrorListener.syntaxError(ProxyErrorListener.java:41) at com.alibaba.qlexpress4.a4runtime.Parser.notifyErrorListeners(Parser.java:544) at com.alibaba.qlexpress4.a4runtime.DefaultErrorStrategy.reportFailedPredicate(DefaultErrorStrategy.java:344) at com.alibaba.qlexpress4.a4runtime.DefaultErrorStrategy.reportError(DefaultErrorStrategy.java:142) at com.alibaba.qlexpress4.aparser.QLParser.nextStatement(QLParser.java:469)

Contributor guide

Research direction
Investigate the parser's token definitions and add support for Unicode mathematical operators such as ≠, ≥, ≤. Modify the grammar file (ANTLR) to include these operators and update the corresponding lexer rules.
Tech stack
java
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
JavaANTLR
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
45