I am creating an alternative function of `IntegerQ[]` function. Now I don't want any output. I just want my function to check whether this is integer or not. I'm gonna use it in another code. My code looks like; IntQ[n_] := Block[{}, GP = 0; {j = 0; If[n >= 0, For[i = n, i > 0, i--, j++], For[i = (-n), i > 0, i--, j++]]}; {If[j == n, True, False]}; ] It is not working. I just want to know where is the problem, why the problem is causing and how to solve it? Generally `IntegerQ[6]` would return True as an output and in other function it wouldn't return anything but we can use that value actually. So that's where my problem is.