Incrementing styles (x = x++) vs (x +=1) - when to use them

This is a discussion on Incrementing styles (x = x++) vs (x +=1) - when to use them within the C Programming forums, part of the General Programming Boards category; I understand that ++x; is a prefix expression and x++; is a postfix. What I can't grasp the concept of ...

  1. #1
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    Incrementing styles (x = x++) vs (x +=1) - when to use them

    I understand that ++x; is a prefix expression and x++; is a postfix.

    What I can't grasp the concept of is the difference between:

    x = x++; vs. x++;

    Also, while I'm comparison shopping, why use x++; or ++x; as opposed to x = +=1; ?

    If anyone has the time, can you break down the do's and don'ts of:

    x = x++;
    x++;
    x +=1;


    ??

    thanks!
    Last edited by vertigoat; 10-04-2012 at 08:18 AM.

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    Quote Originally Posted by vertigoat
    What I can't grasp the concept of is the difference between:

    x = x++; vs. x++;
    The former results in undefined behaviour; the latter is probably what you wanted to write.

    Quote Originally Posted by vertigoat
    Also, while I'm comparison shopping, why use x++; or ++x; as opposed to x = +=1; ?
    My reasoning is that they are more concise and people are used to them. Otherwise, no big deal. It might even be the case on certain hardware with certain non-optimising compilers that the prefix/postfix operators result in code that is more efficient, but that's generally not a concern.
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    don't: x = x++; (undefined behavior)
    do: x++; or ++x; (either one is valid and acceptable)
    do or don't: x += 1; (valid but not as concise as x++)

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    Thank you! Totally understood now.

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