Best way to store a global constants file?

I'm familiar with VB.NET projects in storing global constants, but what is the best way to store them n a C++ project? For example, several files in the project uses the same constants. I use to throw it all into a header, then just include that header wherever needed. Is that the most suggested way if you have several constants?

Probably. You might want to use "#ifndef" style header guards.

Code:

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#ifndef THISPARTICULARHEADER
#define THISPARTICULARHEADER 1
[...everything here...]
#endif

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I don't see why you would need global constants that would apply across the entire application.

Normally if I use a constant then I include the enumeration or const in the header for the interface. In this way the constants and enums are only exposed to those who are implementing the interface which should be the only objects that actually need to use the constants. As well the interface, consts, and enumerations are inside of a namespace. You should not need a file that only contains globals for the rest of the application.

Quote:

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Originally Posted by MK27

Probably. You might want to use "#ifndef" style header guards.

Code:

---

#ifndef THISPARTICULARHEADER
#define THISPARTICULARHEADER 1
[...everything here...]
#endif

---

---

Thanks, MK.

That is a simple include guard. It does not address your possible design issues.

#pragma once works on MSVS 2005+

Quote:

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Originally Posted by MK27

Probably. You might want to use "#ifndef" style header guards.

Code:

---

#ifndef THISPARTICULARHEADER
#define THISPARTICULARHEADER 1
[...everything here...]
#endif

---

---

Normally I use this format:

#ifndef _MYHEADER_H_
#define _MYHEADER_H_
// code here
#endif

Does this do the same thing as the above if I don't put "1" after it?

The value is negotiable, but you shouldn't use a leading underscore.

Soma

Quote:

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Does this do the same thing as the above if I don't put "1" after it?

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Yes, macros can be defined but have no value.

EDIT: got beat to it. I ought to make a habit of refreshing before I reply.

Quote:

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Originally Posted by dxfoo

Does this do the same thing as the above if I don't put "1" after it?

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Nah, that's a paranoid habit of mine I think (it will still be defined).

I've ran into issues where just doing #ifndef blocks in the header doesn't quite cut it.

Rather, in the header do extern const <datatype> variablename, and in a second cpp globals file do all your constants.


[edit]Ah now I remember why I had to do that. The globals where function pointers, and the functions where defined elsewhere. I had to move the function pointers into the file with the functions they where pointing to and declare the extern in the global file.. It was somewhat a mess (It was all for the purpose of being able to redefine functions... I don't know if it was terribly useful, but it was what it was). A regular ifndef block should work well enough, unless you want to do something fancy.[/edit]