表达式语法检查错误，"OR(1<2, 2>3)" 语法检查正确，"or(1<2, 2>3)" 语法检查错误。

表达式语法检查错误，"OR(1<2, 2>3)" 语法检查正确，"or(1<2, 2>3)" 语法检查错误。

```java

private boolean syntaxCheck(String express){
try {
ExpressRunner runner = new ExpressRunner(false, true);
DefaultContext context = new DefaultContext<>();
InstructionSet set = runner.parseInstructionSet(express);
} catch (Exception e) {
return false;
}
return true;
}
```

```json
[{
"value_of_expectation": true,
"formula":"OR(1<2, 2>3)"
},
{
"value_of_expectation": true,
"formula":"or(1<2, 2>3)",
"remark": "小写的or会存在误判"
}]
```

Start by reproducing the two expressions with the shown ExpressRunner.parseInstructionSet call and compare the parser results for uppercase and lowercase OR. Trace the syntax-check path from ExpressRunner, then confirm that both expressions are accepted without changing the behavior of the reported Java entry point.

Written by the indexing model from the issue text.