Basic Typedef question

This is a discussion on Basic Typedef question within the C++ Programming forums, part of the General Programming Boards category; Whats the difference between doing: Code: typedef struct myStruct { int a; int b; }; and Code: typedef struct { ...

  1. #1
    Registered User
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    Basic Typedef question

    Whats the difference between doing:

    Code:
    typedef struct myStruct {
    
          int a;
          int b;
    };
    and

    Code:
    typedef struct {
          int a;
          int b;
    } myStruct;
    They both seem to do the same thing and produce the same results:

    Code:
    myStruct ms;
    ms.a = 3;
    ms.b = 4;

  2. #2
    Algorithm Dissector iMalc's Avatar
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    You don't need the typedef in the first case there.
    Yes they are the same but the first one without the typedef is the preferred way in C++.
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  3. #3
    Captain Crash brewbuck's Avatar
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    You should be getting a warning for the first version. It doesn't actually typedef anything. If you replace the struct {} part with a simpler type, say "int," it would look like:

    Code:
    typedef int;
    Which is meaningless, and I'm surprised it does compile at all (it does compile though, at least with VC9)
    Code:
    //try
    //{
    	if (a) do { f( b); } while(1);
    	else   do { f(!b); } while(1);
    //}

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