Preprocessor Wraper

[Bryan Parkoff]

I am curious. How can you reproduce compiler error if preprocessor
wraper is not omited. It may cause to include a copy of header twice or
more. Please write a short sample code like this.

//Test.h
//#ifndef TEST_H
//#define TEST_H

class A
{
public:
void run( void );

private:
int x;
int y;
};

//endif // TEST_H

--

Yours Truly,
Bryan Parkoff

[Mirco Wahab]

Re: Preprocessor Wraper

Bryan Parkoff wrote:

I am curious. How can you reproduce compiler error if preprocessor
wraper is not omited. It may cause to include a copy of header twice or
more. Please write a short sample code like this.
>
//Test.h
[snipped]

What is that good for? What would be wrong with
a solution like this one? ==>

// Test.h
//#ifndef TEST_H
//#define TEST_H

class A {
// ...
// ...
};

#ifndef TEST_H
#error preprocessor wraper is omited
#endif


//#else
// #error hehe TEST_H included alot
//#endif // TEST_H

<==

Regards

M.

[James Kanze]

Re: Preprocessor Wraper

On Jun 10, 10:44 pm, Mirco Wahab <wa...@chemie.u ni-halle.dewrote:

Bryan Parkoff wrote:

I am curious. How can you reproduce compiler error if
preprocessor wraper is not omited. It may cause to include
a copy of header twice or more. Please write a short sample
code like this.

//Test.h
[snipped]

What is that good for?

You might want to add something like that to your test suite.
Of course, it's pretty easy to do, just include the header twice
in one of your test programs.

(I'll admit that I've never done so. But of course, in any
reasonable environment, the include guards are generated
automatically by the editor when you create the file.)

--
James Kanze (GABI Software) email:james.kan ze@gmail.com
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