Checking for null before pointer usage

Question

Most people use pointers like this...

if ( p != NULL ) {
  DoWhateverWithP();
}

However, if the pointer is null for whatever reason, the functi

Answer 1

This non-NULLness check can be avoided by using references instead of pointers. This way, the compiler ensures the parameter passed is not NULL. For example:

void f(Param& param)
{
    // "param" is a pointer that is guaranteed not to be NULL      
}

In this case, it is up to the client to do the checking. However, mostly the client situation will be like this:

Param instance;
f(instance);

No non-NULLness checking is needed.

When using with objects allocated on the heap, you can do the following:

Param& instance = *new Param();
f(*instance);

Update: As user Crashworks remarks, it is still possible to make you program crash. However, when using references, it is the responsibility of the client to pass a valid reference, and as I show in the example, this is very easy to do.