How to Properly Initialize Constant Data Members in C ?

Initializing Constant Data Members

In C programming, constant data members are used to define values that cannot be modified after initialization. When attempting to initialize a const data member within the class definition, you may encounter errors due to C 's restrictions.

Error Explanation

The compiler error is caused because C prohibits the initialization of const data members within the class definition. This is to prevent multiple definitions of the same data member in different translation units.

Solution: Initialization Outside the Class

To initialize a const data member, it must be defined outside the class definition. This can be achieved using the initializer list in the constructor, as shown below:

#include <iostream>

using namespace std;

class T1 {
  const int t;  // Declaration of const data member

public:

  T1() : t(100)  // Initialization in initializer list
  {
    cout <p><strong>Initializer List</strong></p>
<p>The initializer list within the constructor initializes the const data member before the class initialization. This allows the value to be assigned before the class object is created.</p>
<p><strong>Further Considerations</strong></p>
<p>It is important to note that initializing a const data member using the initializer list must be done within the constructor, and it cannot be modified later in the program.</p></iostream>

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