Tackling the Arrow head Anti-Pattern

Frequently you will see following type of code in your code base.

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if(result != 1) {     if(someOtherResult == 101)     {         if(anotherValue == 500)         {             // do something         }     }     else     {         // do some other thing     } } return;

Here the code forms a shape of an arrow-head, as below:

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if     if         if             if                 do something             end         end     end end

If you see, the main logic is deep down into the nested condition, it increases the cyclomatic complexity of the code.

A better version of the same code could be as below:

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if(result == 1) {     return; } if(someOtherResult == 101 && anotherValue == 500) {     // do something     return; } // do some other thing return;

The above code does a number of things to flatten the code and make it better:

1. Validations are performed first and it returns at the first opportunity.
2. Multiple nested conditions are combine into one (with “&&”(logical And) operator. If there are multiple expressions forming one such condition, they can be moved to a separate method returning boolean. That method can then be use in the if condition as below:

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if(IsValidResult(someOtherResult, anotherResult) {     // do something     return; } bool IsValidResult(int someOtherResult, int anotherResult) {     if(someOtherResult == 101 && anotherValue == 500)     {         return true;     }     return false; }