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Can I get the address of a constant?

Posted on 2003-11-24
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Last Modified: 2010-04-02
Hi!

I have something like this:

#define MYCONST 666

Since I want the constant to become a key in a mapping class that expects void-pointers I thought I could hand over the address of MYCONST, but

&MYCONST

produces a compiler error.

Is there any way to reference the address of MYCONST in C++?

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Question by:hirnsieb
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jkr earned 500 total points
ID: 9811062
>>Is there any way to reference the address of MYCONST in C++?

Not in the way you are using it - the above is a preprocessor macro that tells the compiler to replace every occurance of MYCONST with 666. It would work if you'd use

const MYCONST = 666;
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Expert Comment

by:SteH
ID: 9811070
#define is something for the preprocessor. It will be translated before the compiler works to:
&666. This is not a legal C/C++ statement.


Declare it as a constant not as a preprocessor macro:

const int MYCONST = 666;

now &MYCONST is legal.
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Expert Comment

by:RJSoft
ID: 9811240
Or

int *Myconst = MYCONST;

printf(" address is %x", Myconst);

RJ
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