Lexical error at line 1 while checking: [C, 9, 7] ^ The value for Attribute 'Metaonly' must be numeric.
Somehow, a non-numeric value has been assigned to a numeric attribute. Perhaps this was a result of something you did in typescript, a button script, or assignment to the attribute in one of your own meta-inference algorithms. It would be unusual for this to happen under normal usage.
You can clear the attribute from the typescript window by typing:
With nothing following the colon, where «att» is the attribute name and «obj» is the identifier of the object. For example:
More important that just remedying this once, you probably want to figure out how it got changed to a non-numeric value in the first place. It may indicate a bug in your meta-inference logic, for example.