> The Ada people call their headers 'specifications', because a lot of > program specifications are placed in those headers. > > But they are not specifications in a sense that you can have multiple > implementations of them. I.e. there is a 1-to-1 correspondence between > Ada package declarations and package bodies. > > Feel free to correct me if I am mistaken.
You are mistaken. ;-) It's not uncommon to have multiple different implementations of the same specification, for example for different target architectures or one might be production and the other development.