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Comment by mekazu | Hacker News Reader

> Therefore, this line actually says:

    !didIMakeAMistake() || CIsWrongHere();

> If you understand how short-circuit evaluation works, you can understand that this will result in the following:

   if (!didIMakeAMistake()) 
      CIsWrongHere();

Can someone explain this? I’d have thought that was right without the !

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It must be a typo.

Function calls have the highest priority here, followed by logic NOT and logic OR.

    !didIMakeAMistake() || CIsWrongHere();

!didIMakeAMistake() is evaluated first (or you can say didIMakeAMistake() is executed and evaluated first, then its result is inverted and checked), if it's true, evaluation is finished. If it's false, CIsWrongHere(); is evaluated.

It is indeed equivalent to

   if (didIMakeAMistake())  /* !didIMakeAMistake() == false? */
      CIsWrongHere();

Without the invertion.

Thank you guys so much! I've changed it immediately.

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