Great! Please report it as a Github issue!

If the bug is with a specific formula/excel file, please include that too.
Generally bugs in XLParser are one of the following, please include this type in the report:

• The parser can't parse a formula that Excel accepts
• The parser parses a formula that Excel doesn't accept.
• The parser interprets a formula wrong, that is it produces a parse tree that doesn't correspond with how Excel behaves.
• There is a "normal" bug in the code around the core parser.