How to avoid “if” chains?

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Assuming I have this pseudo-code:

bool conditionA = executeStepA();
if (conditionA){
    bool conditionB = executeStepB();
    if (conditionB){
        bool conditionC = executeStepC();
        if (conditionC){
            ...
        }
    }
}

executeThisFunctionInAnyCase();

Functions executeStepX should be executed if and only if the previous succeed.
In any case, the executeThisFunctionInAnyCase function should be called at the end.
I’m a newbie in programming, so sorry for the very basic question: is there a way (in C/C++ for example) to avoid that long if chain producing that sort of “pyramid of code”, at the expense of the code legibility?

I know that if we could skip the executeThisFunctionInAnyCase function call, the code could be simplified as:

bool conditionA = executeStepA();
if (!conditionA) return;
bool conditionB = executeStepB();
if (!conditionB) return;
bool conditionC = executeStepC();
if (!conditionC) return;

But the constraint is the executeThisFunctionInAnyCase function call.
Could the break statement be used in some way?

50 Answers
50

You can use an && (logic AND):

if (executeStepA() && executeStepB() && executeStepC()){
    ...
}
executeThisFunctionInAnyCase();

this will satisfy both of your requirements:

  • executeStep<X>() should evaluate only if the previous one succeeded (this is called short circuit evaluation)
  • executeThisFunctionInAnyCase() will be executed in any case

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