Page 314 - DCAP404 _Object Oriented Programming

Unit 14: Advanced Concept in C++

W < int , 10 > + twoptr = & one ; // No object is created Notes
W < int, 10 + 3 > three = 200; // Displays a = 230
W < float, 40 > four = 100.45 ; // Displays a = 140.45
Return 0;
}

Rules for Using Templates

Listed below are the rules for using templates:
1. The name of a parameter can appear only once within a formal parameter list. For example:
Template <class type>
Type max ( type a, type b)

{
return a > b ? a : b ;
}
2. The keyword, class must be specified before the identifier.
3. Each of the formal parameters should form a part of the signature of the function. For
example:

Template < class T >
Void func ( T a )
{
......
}
4. Templates cannot be used for all overloaded functions. They can be used only for those
functions whose function body is the same and argument types are different.

5. A built-in data type is not to be given as a template argument in the list for a template
function but the function may be called with it. For example:
Template < class ZZ , int > // wrong

Void fn ( ZZ , int) ;
Template < class Z > // right
Void fn ( ZZ , int ) ;
6. Template arguments can take default values. The value of these arguments become constant
for that particular instantiation of the template.

Example:
Template < class X , int var = 69 >
Class Aclass
{
public :

void func ( )

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