Chapter 17.1, Problem 6STE

Program Plan Intro

Function template:

In C++, a function template is referred as a “generic” function, which can work with different data types.

• While writing a function template, a programmer should use a “type parameter” to denote a “generic” data type instead of using the actual parameter.
• The compiler generates the code, when it encounters a function call to a function template. This code will handle the particular data type which is used in the function call.
• The compiler identifies the argument type and generates the code to work with those types.
• The generated code is referred as “template function”.

Example:

For example consider the following function template for finding a cube of value:

  template <class T>

  T cube(T x)

  {

  return x * x * x ;

  }

• A function template must begin with the keyword “template” and it is followed by a pair of angle brackets, which contains one or more “generic” data types.
• A “generic” type must start with the keyword “class”, followed by an argument name which stands for the data type.
• The statement “T cube(T x)” is referred as function header, where “T” is a “type parameter”, “cube” is the function name and the variable “x” is declared for the type “T”.