Problems with static const class members

This is a discussion on Problems with static const class members within the C++ Programming forums, part of the General Programming Boards category; For some reason the following code gives me a "syntax error before numeric constant" error on compile in dev-c++ Code: ...

  1. #1
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    Problems with static const class members

    For some reason the following code gives me a "syntax error before numeric constant" error on compile in dev-c++

    Code:
    class Heuristic // abstract
    {
        public:
            virtual int distanceFromOptimal(State* b) = 0;
            virtual int optimalValue() = 0;
            virtual int optimalDirection() = 0;
            
            const static int INFINITY;
            static const int INCREASE;
            static const int DECREASE;
    };
    even though this code compiles with no errors

    Code:
    class State
    {
        public:
            const static string STATE_TYPE; // to identify problem specific states
    };
    Anyone got any ideas why?

    Also I've read in my c++ book that static variables have only file scope at most, does this affect class members in any way?
    Last edited by sigfriedmcwild; 12-04-2004 at 03:47 PM.

  2. #2
    carry on JaWiB's Avatar
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    Apparently INFINITY is already defined somewhere...Try not using all caps for your variable names...
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  3. #3
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    I used all caps since those are supposed to be constants (kind of like when you use all caps for defines)

    Still when I try to use any of those constants outside Heuristic class I get a "syntax error before ; token"

    code like this gives errors
    Code:
    return Heuristic.INCREASE;
    or
    Code:
    int a = Heuristic.DECREASE;
    since the variables are static I should be able to access them without constructing an object, using classname.varname right?
    Last edited by sigfriedmcwild; 12-04-2004 at 07:30 PM.

  4. #4
    Code Goddess Prelude's Avatar
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    >since the variables are static I should be able to access them without constructing an object
    Yes.

    >using classname.varname right?
    No. You would use classname::varname.
    My best code is written with the delete key.

  5. #5
    Registered User manofsteel972's Avatar
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    Where do you initialize them with values? until you initialize a static member it doesn't exist.

    try
    Code:
    int Heuristic::INCREASE=0;
    Last edited by manofsteel972; 12-04-2004 at 07:54 PM.
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    thx prelude

    @manofsteel972 - I did do that in the .cpp file

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