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// Fig. 3.12: fig03_12.cpp
// A scoping example.
#include <iostream>
using std::cout;
using std::endl;
void useLocal( void ); // function prototype
void useStaticLocal( void ); // function prototype
void useGlobal( void ); // function prototype
int x = 1; // global variable
int main()
{
int x = 5; // local variable to main
cout << "local x in main's outer scope is " << x << endl;
{ // start new scope
int x = 7;
cout << "local x in main's inner scope is " << x << endl;
} // end new scope
cout << "local x in main's outer scope is " << x << endl;
useLocal(); // useLocal has local x
useStaticLocal(); // useStaticLocal has static local x
useGlobal(); // useGlobal uses global x
useLocal(); // useLocal reinitializes its local x
useStaticLocal(); // static local x retains its prior value
useGlobal(); // global x also retains its value
cout << "\nlocal x in main is " << x << endl;
return 0; // indicates successful termination
} // end main
// useLocal reinitializes local variable x during each call
void useLocal( void )
{
int x = 25; // initialized each time useLocal is called
cout << endl << "local x is " << x
<< " on entering useLocal" << endl;
++x;
cout << "local x is " << x
<< " on exiting useLocal" << endl;
} // end function useLocal
// useStaticLocal initializes static local variable x only the
// first time the function is called; value of x is saved
// between calls to this function
void useStaticLocal( void )
{
// initialized first time useStaticLocal is called.
static int x = 50;
cout << endl << "local static x is " << x
<< " on entering useStaticLocal" << endl;
++x;
cout << "local static x is " << x
<< " on exiting useStaticLocal" << endl;
} // end function useStaticLocal
// useGlobal modifies global variable x during each call
void useGlobal( void )
{
cout << endl << "global x is " << x
<< " on entering useGlobal" << endl;
x *= 10;
cout << "global x is " << x
<< " on exiting useGlobal" << endl;
} // end function useGlobal
/**************************************************************************
* (C) Copyright 1992-2003 by Deitel & Associates, Inc. and Prentice *
* Hall. All Rights Reserved. *
* *
* DISCLAIMER: The authors and publisher of this book have used their *
* best efforts in preparing the book. These efforts include the *
* development, research, and testing of the theories and programs *
* to determine their effectiveness. The authors and publisher make *
* no warranty of any kind, expressed or implied, with regard to these *
* programs or to the documentation contained in these books. The authors *
* and publisher shall not be liable in any event for incidental or *
* consequential damages in connection with, or arising out of, the *
* furnishing, performance, or use of these programs. *
*************************************************************************/
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