Thanks, that was exactly what I was looking for.
Basically, I wasn't sure whether I could omit the parentheses in an expression of the type:
(A and B) or (C and D)
or:
(A or B) and (C or D)
I now see that, because of precedence, I can omit parentheses in the first case, but not in the second.
Hilmar.
>1) Precedence
>
>( )
>
>NOT, !
>
>AND
>
>OR
>
>
>(2) documented in the help under
Logical Operators
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)
