Accessing Globals With Same Name

This is a discussion on Accessing Globals With Same Name within the C Programming forums, part of the General Programming Boards category; I want to ask how do we access the global variables if we know that the same name also occurs ...

  1. #1
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    Accessing Globals With Same Name

    I want to ask how do we access the global variables if we know that the same name also occurs in the local function. So according to C local function with override the global but what if i want to access the global variable's value. Also the same problem occurs if i nest certain statements and use the same variable name throughout then how am i going to get the specific value as per level. eg.
    [Code]
    int a=11;
    int main()
    {
    int a=10;
    {
    int a=5;
    {
    int a=4;
    {
    int a=3;
    printf("%d",a);//How can i access other values of a from here
    }
    }
    }

    }

    Thanks in advance

  2. #2
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    I don't have a clue but surely it would be easier just to give the variables different names?

    edit: you could do this if you really want to:
    Code:
    int foo = 1;
    int *pf = &foo;
    
    {
       int foo = 2;
       printf("%d, %d", foo, *pf);
    }
    Last edited by Brian; 07-21-2006 at 03:05 AM.

  3. #3
    Devil's Advocate SlyMaelstrom's Avatar
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    I don't know for C, but in C++ you can use the scope resolution operator, by itself. C might actually have no implementation of an operator or function to do such a thing. I'm not the person to ask, though.
    Sent from my iPadŽ

  4. #4
    Yes, my avatar is stolen anonytmouse's Avatar
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    There is no way. As Brian said, you need to use different variable names. Some people prepend global variables with g_, as in g_foo to differentiate them from local variables. Another method is to put your global variables in a static structure, so they are accessed globals.foo. Both these methods can make code more readable as it makes it immediately clear that a variable is a global.

  5. #5
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    That would result in a kind of Systems Hungarian Notation, where the first letter of the variable name indicates the scope, the second the data type, then after an underscore comes the name of the variable.

    So here you'd have gi_foo (global integer called foo) and li_foo (local integer called foo).

    People have mixed feelings about this, as styles get mixed up and it can lead to more confusion, not less under certain circumstances.

    Even so, using the same name and trying to get a variable of the same name from a parent's scope (even if it was possible) can make for some pretty unreadable code!
    I think you can put a signature here.

  6. #6
    pwns nooblars
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    Never thought of using a struct to hold globals, that is a good idea!

  7. #7
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    Quote Originally Posted by SlyMaelstrom
    I don't know for C, but in C++ you can use the scope resolution operator, by itself. C might actually have no implementation of an operator or function to do such a thing. I'm not the person to ask, though.

    I recognize that in C++ there is a scope resolution operator but whenever it is called it only calls the global and doesn't pay heed to local nested variables. But is there a way to do it in C++, if yes then please clarify

  8. #8
    Code Goddess Prelude's Avatar
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    >But is there a way to do it in C++, if yes then please clarify
    Yes, there is. Don't reuse identifiers from an enclosing scope. It's just that simple.
    My best code is written with the delete key.

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