Thread: templating with inheritance

  1. 05-27-2008 #16
    mickey0
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    hi,

    then could you make me some examples when it's suggested to use forward declaration (to improve speed compilation)?
    thanks
  2. 05-28-2008 #17
    Elysia
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    For small projects, you rarely have to worry about it. Otherwise, as many forward declarations as possible where permitted will improve performance.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.
  3. 05-28-2008 #18
    mickey0
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    what I worndered is "what" I can/must declare with "forward declaration" (eg. vector seems not)
  4. 05-28-2008 #19
    Elysia
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    Any of your own classes.
    For any STL and standard library, you must use "forward headers" if they exist (headers that contain forward declarations). Otherwise you're out of luck.
    But precompiled headers can usually help here, by putting those headers inside the PCH.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.
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