Should C++ eliminate header files? [closed]

Answer 1

One advantage of this separation is that it is easy to view only the interface, without requiring an advanced editor.

Answer 2

No language exists without header files. It's a myth.

Look at any proprietary library distribution for Java (I have no C# experience to speak of, but I'd expect it's the same). They don't give you the complete source file; they just give you a file with every method's implementation blanked ({} or {return null;} or the like) and everything they can get away with hiding hidden. You can't call that anything but a header.

There is no technical reason, however, why a C or C++ compiler could count everything in an appropriately-marked file as extern unless that file is being compiled directly. However, the costs for compilation would be immense because neither C nor C++ is fast to parse, and that's a very important consideration. Any more complex method of melding headers and source would quickly encounter technical issues like the need for the compiler to know an object's layout.

Answer 3

In The Design and Evolution of C++, Stroustrup gives out one more reason...

The same header file can have two or more implementation files which can be simultaneously worked-upon by more than one programmer without the need of a source-control system.

This might seem odd these days, but I guess it was an important issue when C++ was invented.

Answer 4

If you want C++ without header files then I have good news for you.

It already exists and is called D (http://www.digitalmars.com/d/index.html)

Technically D seems to be a lot nicer than C++ but it is just not mainstream enough for use in many applications at the moment.

Answer 5

I routinely flip between C# and C++, and the lack of header files in C# is one of my biggest pet peeves. I can look at a header file and learn all I need to know about a class - what it's member functions are called, their calling syntax, etc - without having to wade through pages of the code that implements the class.

And yes, I know about partial classes and #regions, but it's not the same. Partial classes actually make the problem worse, because a class definition is spread across several files. As far as #regions go, they never seem to be expanded in the manner I'd like for what I'm doing at the moment, so I have to spend time expanding those little plus's until I get the view right.

Perhaps if Visual Studio's intellisense worked better for C++, I wouldn't have a compelling reason to have to refer to .h files so often, but even in VS2008, C++'s intellisense can't touch C#'s

Answer 6

Header files allow for independent compilation. You don't need to access or even have the implementation files to compile a file. This can make for easier distributed builds.

This also allows SDKs to be done a little easier. You can provide just the headers and some libraries. There are, of course, ways around this which other languages use.