SYMPTOM:
When using an attribute form with special characters (including '-','/','(',')') in a custom expression filter object, the following error is received when validating the expression:
Sample Code/Error
Attribute form specified with an attribute was not found among the attribute's forms
CAUSE:
When an attribute form's name contains special characters, it is required to add a pair of square brackets around it to properly validate the expression
ACTION:
After adding square brackets to the attribute form's name, the expression can be validated properly, as shown below:
