Codice di esempio per PCH
Gli esempi riportati di seguito sono utilizzati nel makefile illustrato in File PCH nel processo di compilazione e Makefile di esempio per PCH. I commenti contengono importanti informazioni.
// ANOTHER.H : Contains the interface to code that is not
// likely to change.
//
#ifndef --ANOTHER_H
#define --ANOTHER_H
#include<iostream>
void savemoretime( void );
#endif // --ANOTHER_H
// STABLE.H : Contains the interface to code that is not likely
// to change. List code that is likely to change
// in the makefile's STABLEHDRS macro.
//
#ifndef --STABLE_H
#define --STABLE_H
#include<iostream>
void savetime( void );
#endif // --STABLE_H
// UNSTABLE.H : Contains the interface to code that is
// likely to change. As the code in a header
// file becomes stable, remove the header file
// from the makefile's UNSTABLEHDR macro and list
// it in the STABLEHDRS macro.
//
#ifndef --UNSTABLE_H
#define --UNSTABLE_H
#include<iostream.h>
void notstable( void );
#endif // --UNSTABLE_H
// APPLIB.CPP : This file contains the code that implements
// the interface code declared in the header
// files STABLE.H, ANOTHER.H, and UNSTABLE.H.
//
#include"another.h"
#include"stable.h"
#include"unstable.h"
// The following code represents code that is deemed stable and
// not likely to change. The associated interface code is
// precompiled. In this example, the header files STABLE.H and
// ANOTHER.H are precompiled.
void savetime( void )
{ cout << "Why recompile stable code?\n"; }
void savemoretime( void )
{ cout << "Why, indeed?\n\n"; }
// The following code represents code that is still under
// development. The associated header file is not precompiled.
void notstable( void )
{ cout << "Unstable code requires"
<< " frequent recompilation.\n"; }
// MYAPP.CPP : Sample application
// All precompiled code other than the file listed
// in the makefile's BOUNDRY macro (stable.h in
// this example) must be included before the file
// listed in the BOUNDRY macro. Unstable code must
// be included after the precompiled code.
//
#include"another.h"
#include"stable.h"
#include"unstable.h"
int main( void )
{
savetime();
savemoretime();
notstable();
}