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Passing array address through a class function

 
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Passing array address through a class function
lichmaster03
post 13 Mar, 2008 - 10:03 AM
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I am getting this warning when compiling.

QUOTE
warning C4700: uninitialized local variable 'p' used


These are the functions that use 'p'.

CODE
void Grid::init(Array mary){

    Cell ***p;
    
    mary.tempPointer(p, mary);
    
    d = (mary.getD())/2;
    r = (mary.getR())/2;
    c = (mary.getC())/2;

    p[d][r][c].current();
}
void Array::tempPointer(Cell ***p, Array mary){
    p = mary.ary;
}


Any help will be greatly appreciated.
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Bench
post 13 Mar, 2008 - 10:40 AM
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You're passing the pointer by value. This means your Array::tempPointer function isn't modifying the original pointer object, but making a copy instead, so the original remains uninitialised after the call to tempPointer.

If you wish to modify the original, then possibly the simplest way is to pass by reference;
cpp
void Array::tempPointer(Cell& ***p, Array mary){
	p = mary.ary;
}

I'd probably also question why you're using a pointer-to-pointer-to-pointer, but that's a separate issue altogether

This post has been edited by Bench: 13 Mar, 2008 - 10:42 AM
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lichmaster03
post 13 Mar, 2008 - 01:03 PM
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Thanks for the help but now I'm having trouble getting the address of p to match the address of mary.ary.

CODE
Grid::Grid(Array &mary){
    this->init(mary);
}
void Grid::init(Array &mary){
    
    p = mary.tempPointer(mary);
    
    d = (mary.getD())/2;
    r = (mary.getR())/2;
    c = (mary.getC())/2;

    p[d][r][c].current();

    cout << '\n' << p;
}
Cell*** Array::tempPointer(Array& mary){
    return mary.ary;
}


I passed the array by reference so p could = mary.ary but the addresses dont match when I print them.

This post has been edited by lichmaster03: 13 Mar, 2008 - 01:03 PM
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