Example Code for PCH
The following examples are used in the makefile described in PCH Files in the Build Process and Sample Makefile for PCH. Note that the comments contain important information.
// 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();
}