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Thread: pointer in a class

  1. #21
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    Default Re: pointer in a class

    Is it really worth the trouble? Use precompiled headers and your problem will disappear (along side a 100MB of your disk space).

  2. #22
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    Default Re: pointer in a class

    Quote Originally Posted by wysota View Post
    Is it really worth the trouble? Use precompiled headers and your problem will disappear (along side a 100MB of your disk space).
    When I start to do this forward declaration, I didn't think it was "particularly". What I'd like understand to this point is:
    1. Why these all problems
    2. why 100MB !!!
    3. When Does the forward declaration is recommended

    Thanks in advance.
    Regards

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    Default Re: pointer in a class

    Quote Originally Posted by mickey View Post
    1. Why these all problems
    You should know, it's your code

    2. why 100MB !!!
    When you use precompiled headers this is more or less the amount of spaces those headers take after precompilation.

    3. When Does the forward declaration is recommended
    We've been all over this question... It's not recommended in this particular case, just include the vector and skip to some more interesting work.

  4. #24
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    Default Re: pointer in a class

    Concerning (1) -- because STL container classes use enough template magic that forward-declaring them is a pain.

    As for (3) -- forward declaration is mostly to speed up compilation times. Precompiled headers take care of that problem to some extent by only compiling the header part once, eliminating most of the overhead (so that the vector header doesn't need to be parsed every time a file is compiled that includes your class header that uses it).

    In this case, obviously the effort to forward-declare a vector isn't worth the small time savings during compilation.

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