Here in an interesting thing I found today. I have attached a sample file. I have used a list () on some let variables in a calc.

This behavior could possibly be associated with this recent thread but I dont think directly.

http://fmforums.com/forum/showtopic.php?tid/186557

List_Test.zip

What's should we be looking for?

Sorry Mike. I thought that the example would explain it.

The list () returns a value of 0 if a flag boolean field is zero where a test is made as such: Case ( flg_car; "Car" ).

It will return

House

0

Job

However if Case ( GetAsBoolean ( flg_car ); "Car" ) is used, then it returns null.

House

Job

So I tested it as a concat thinking that the let was passing the value zero. However, it returns null, as the concat returns "HouseJob".

So why does using the list function return a zero instead of the null when GetAsBoolean is not used?

It looks like a bug to me. The variable should be empty, and probably classified as Text. Note that the problem goes away if the variable is expressly defined as Text.

I am guessing something in the order of evaluation causes the variable to be forced into a number, under these particular circumstances.