avoiding if statements

I was thinking about object oriented design today, and I was wondering if you should avoid if statements. My thought is that in any case where you require an if statement you can simply create two objects that implement the same method. The two method implementations would simply be the two possible branches of the original if statement.

I realize that this seems extreme, but it seems as though you could try and argue it to some extent. Any thoughts on this?

EDIT

Wow that didn't take long. I suppose this is way too extreme. Is it possible to say though, that under OOP you should expect way less if statements?

SECOND EDIT

What about this: An object that determines its method implementation based on its attributes. That is to say you can implement someMethod() in two ways and specify some restrictions. At any point an object will route to the correct method implementation based on its properties. So in the case of if(x > 5) just have two methods that rely on the x attribute

Solution 1:

I can tell you one thing. No matter what people say, thinking about simplifying and eliminating unnecessary branching is a sign of you maturing as a software developer. There are many reasons why branching is bad, testing, maintenance, higher rate of bugs and so on. This is one of the things I look for when interviewing people and is an excellent indicator how mature they are as a developer. I would encourage you to keep experimenting, simplifying your code and design by using less conditions. When I did this switch I found much less time debugging my code, it simply worked, then when I had to change something, changes were super easy to make since most of the code was sequential. Again I would encourage you 100% to keep doing what you are doing no matter what other people say. Keep in mind most developers are working and thinking at much lower level and just follow the rules. So good job bringing this up.

Solution 2:

Explain how to implement the following without an if statement or ternary logic:

if ( x < 5 ) {
   x = 0
} else {
   print x;
}

Solution 3:

Yes its true that often complex conditionals can be simplified with polymorphishm. But its not useful all the time. Go read Fowler's Refactoring book to get an idea of when.

http://www.refactoring.com/catalog/replaceConditionalWithPolymorphism.html

Solution 4:

Completely eliminating if statements is not realistic and I don't think that is what Ori is suggesting. But they can often be replaced using polymorphism. (And so can many switch statements).

Francesco Cirillo started the Anti-If Campaign to raise awareness of this issue. He says:

Knowing how to use objects lets developers eliminate IFs based on type, those that most often compromise software's flexibility and ability to evolve.

You or your team can also join the campaign.

Solution 5:

One of my teacher used to say that. I tend to think that people being so dogmatic about that kind of thing usually don't program for a living.