Q:

Why are function argument names unimportant in c++ declarations?

Function argument names in declarations (that most likely reside in the header file) are seemingly completely ignored by the compiler. What are the reasons for allowing the following to compile using either declaration version 1 or 2? 

implementation
void A::doStuff(int numElements, float* data)
{
    //stuff
}

declaration - Version 1
class A
{
public:
    void doStuff(int numElements, float* data);
}

declaration - Version 2
class A
{
public:
    void doStuff(int, float*);
}

A:

The compiler only needs to know what kind of arguments the method requires. It's unimportant for the compiler how you call them.
The compiler needs to know the argument types for several reasons:

Decide which method to use if there are several methods with the same method name
Decide whether the input parameters are valid
Decide whether the parameters need to be casted
Decide how to generate the CODE to call the method and handle the response

However, I suggest to use the first header version. It helps other developers (and yourself) to use the functions and know what parameters have which meaning.

A:

Parameter names aren't part of the function signature. Unless you use them, you don't need to have names even in the function implementation.

A:

Because the names don't affect anything the compiler does outside the function.

