a QuickQuestion about "If () {}"

is there any real reason why some prefer one style over another whyle using them ? :

Code:

         if (col == 1)
            cout << '*';
         else {
            if (col == height * 2)
               cout << '*';
            else
               cout << '0';
         }

and the one below

Code:

         if (col == 1)
            cout << '*';
         else if (col == height * 2)
            cout << '*';
         else
            cout << '0';

the only diference in those 2 that i see is that in first one u can easy add a debug code or so, if the first "if" is false.
is that the only diference and reason that it could make to be better using that style ?(first seems a bit harder to folow but a bit easyer to modifi)

Of the two choices, I'd use neither.

Depending on circumstances I'd be more likely to do something like this

Code:

    if (1 == col || (2*height) == col)
    {
            cout << '*';
    }
    else
    {
            cout << '0';
    }

My "depending on circumstances" clause means that I may do something else depending on what the variables represent, whether the various terms are reused, how clear I wish to be......

Generally I aim for the clearest code that achieves the intended effect.

I usually don't bother with { } when there's a single instruction on conditional/loops statements, I find code to be easier to read like that

Code:

         if (col == 1)
            cout << '*';
         if (col == height * 2)
            cout << '*';
         else
            cout << '0';

That's how I do it.

Since grumpy's code isn't less readable, I would prefer it over yours, since it doesn't duplicate code.

Elysia didnt u posted before grumpy ?(if not, i think my eyes are kinda playing triks on me .. ).
From what i see (and i read here and there) no real diference or inpact if i use first style or 2nd style its only a preference thing and it doese not change how code works.(in my 2 exapls)

Babkockdood is alot diferent than my exapls. He doesent trust logical OR operator so he useses 2x if's.(i mean he doesent trust the order in wich conditions are evaluated)
or more explicit to say .. is that metod is worth using when one of the conditions to be evealuated depends on the other one or when u want/expect a short-circuit.

ty ty all i think a bit clearer about this thing now.

Edit
edited coz my english suks and its a bit harder to type it all ok.
sorry for my english to .

Originally Posted by Flo

Elysia didnt u posted before grumpy ?(if not, i think my eyes are kinda playing triks on me .. ).

Maybe they do

or more explicit to say .. is that metod is worth using when one of the conditions to be evealuated depends on the other one or when u want/expect a shortcut.

I'm not so sure. The && and || operators can short-circuit. That is, if the left-operand is false or true respectively, no more of the expression needs to be evaluated.

or more explicit to say .. is that metod is worth using when one of the conditions to be evealuated depends on the other one or when u want/expect a short-circuit.(if u dont trust the order in wich is evaluated or if u want to be clear that its want/expected the short-circuit)

and btw i typed shortcut instead of short-circuit. My bad .. english problem :P

sorry for that, didnt explained why i said that to clear.

Originally Posted by Babkockdood

Code:

         if (col == 1)
            cout << '*';
         if (col == height * 2)
            cout << '*';
         else
            cout << '0';

That's how I do it.

Too bad your code is not equivalent to those in the original post....

if (1 == col || (2*height) == col)

I detest the order here. Unfortunately the style cops where I work force this upon us even though every single modern compiler will ask you if you really meant == instead of =. Not to mention that an equivalent/assignment bug is about the easiest thing to find in a debugger.

I'm with grumpy, but if the three cases were all different, I'd go for this:

Code:

         if (col == 1) {
            cout << '*';
         } else if (col == height * 2) {
            cout << '+';
         } else {
            cout << '0';
         }

Originally Posted by Bubba

I detest the order here. Unfortunately the style cops where I work force this upon us even though every single modern compiler will ask you if you really meant == instead of =. Not to mention that an equivalent/assignment bug is about the easiest thing to find in a debugger.

i sure understand that and agree with you, as my good friend said that most of the time it is better to be a nice "read-able code" then to be "to-safe code".
coz surely will need to be read/maintained in the future.

Preferably, you should have a mix of the two. Readability helps maintenance. But safe code helps catch bugs and saves time.

I think the practice of switching the order does neither of the above.

Originally Posted by Bubba

I think the practice of switching the order does neither of the above.

Unfortunately, reported results from monitoring programmer activity and objectively measuring productivity by various measures do not agree with you. I remember reading a report from Microsoft that concluded several such techniques do have a positive effect on productivity - even allowing for tendancy of programmers to routinely complain if forced to use those techniques.

A number of psychological studies have also concluded that humans are very poor at judging effectiveness of techniques they use in task-related activities, and often exhibit a strong bias towards using ineffective techniques in the mistaken belief they are most effective.