pcall error diagnosis

@lewis6991 The issue is consistently reproducible in this project, but I cannot extract a minimal example. Moreover, the error message disappear when any character in this file is altered. I suspect there is a problem with the parsing order.

<img width="1278" height="528" alt="Image" src="https://github.com/user-attachments/assets/96bd422a-1065-46ae-b953-3cff67791cf8" />