>>>I needed to be more specific. You said "I tried to write in Expression: TownEnd=.t.". Instead of TownEnd=.T., you should have just put .T. Your function which returns .T. works, so you don't have to replace anything. But it's doing more than you need to.
>>
>> I trully don't understand :( If I put .t. in Expression, what changes?
>>The TownEnd variable doesn't change in this case. I've tried to put in Expression just .t. and nothing changed.
>
>I'm sorry, I guess I don't understand what Expression you're talking about, maybe it's a part of Report Writer I'm not familiar with. I should just stop talking now and say "what you have works, don't change it."
>
>Sorry I jumped in where I didn't really know.

Now I've reread the whole thread, and I know what's going on. You DO need to call a function (or procedure) in the Expression you're talking about. What's not necessary was for you to RETURN TownEnd. All you had to do was change it within the function (or procedure) you called.

Cheers,
Rich.