In LibreOffice calc, what are the rules for using cell function argument which is present (as defined by presence of argument separators), but empty? Is it treated as blank? As zero? As some default value for that function? What is the type of, for example, resulting IF function result? For example:

=IF(0; 1) Result is: FALSE (this one is easy, default value of optional argument is used)

=IF(0; 1;) Result is: 0 (but what is third argument here?)

=IF(1; ; 1) Result is: 0 (or second here?)

=IF(1;) Result is: 0 (or here?)

=ISTEXT(IF(1; ; 1)) Result is: FALSE

=ISNUMBER(IF(1; ; 1)) Result is: FALSE

=IF( IF(1; ; 1) = 0) Result is: TRUE

=IF( IF(1; ; 1) = â€śâ€ť) Result is: TRUE

=CELL(â€śtypeâ€ť; A4) Result is: v (Value, result of a formula as a number)

ISTEXT() and ISNUMBER() claim that result of IF(1; ; 1) is neither text nor number. But CELL(â€śtypeâ€ť; A4), where cell A4 contain either second, third or fourth formula, claim that content of that cell IS number. Also it is treated as equal with both empty string and zero?

What is result of IF function with such arguments? Blank value? Zero? Can we than write â€śreal blank valueâ€ť in a cell with simple IF(1;) expression?