Thank you for your post.
I am able to replicate with both FileMaker Pro 10 and FileMaker Pro 11, on both Windows and Mac OS X machines. If the contents of the calculation field is unstored, then the custom function is evaluated when viewing the records.
Our Development and Software Quality Assurance (Testing) departments are aware of this issue. There has been some discussion about the impact, because custom functions, unlike calculation fields, can be referenced from any table within the database file, so updating all calculation references to the custom function in every table could negatively affect performance.
If you have your original custom function and explain why this needs to change and update, I will make sure it gets attached to the original case.
It's an issue for developers on two levels.
In my case, I was implementing progressively more sophisticated versions of the same custom function, adding additional features one at a time. It is used to populate a field referenced in a value list so it must be stored and indexed. Each time I tweaked the definition to get a better version of the value list, I had to find and modify my calculation expressions in a meaningless way such as appending & "" to the end before the existing calculation field would re-evaluate with the new version of the same function.
- This shouldn't be a performance issue as this only happens when a developer modifies the definition of the function.
- We should at least document this behavior in Filemaker Help so developers can know this is an issure rather than wasting time trying to figure out why a field using a newly redefined custom function didn't evaluate correctly.
It's the only CF defined in the Known Bugs List database and is used to parse text fields into a clean value list of keywords 3 letters or longer and with consistent capitalization: http://www.4shared.com/file/8orL8apk/FMP_Bugs.html
Surely we could at least have a button in Manage | Custom Functions that updates the calculation fields?
Thank you for the explanation and file. I have attached both to the original case so it can be further discussed.
I ran into this problem today. Glad to know that it is known behavior. Please keep me posted if there is a workaround or if this is fixed.
4 1/2 years since first report and it still exists in FMPA 13.0v4 under OSX 10.9.5. Calculations which use a function are supposed to change! That is why we made it a calculation and not auto-enter text.