How does this kind of thing jive with the law on recipes, which can't be copyrighted? Or do I have a layman's misunderstanding of what constitutes a recipe? I would have expected code to be treated much the same way recipes are. Can you generally copyright directions except for recipes? (Maybe on a related note, do/did libraries have to pay license fees for things like shelving according to the Dewey decimal system?)
A written description of a recipe (that you'd find in a cookbook, for example) can most certainly be copyrighted.
As I understand it, what can't be copyrighted is the proportions/ingredients/cooking methods. So if someone writes a new recipe that happens to describe the same dish that someone else's cookbook's recipe would have you make, that is not infringement. But if you copy the recipe from the cookbook, it is.
I am not a lawyer, but I believe you cannot even copyright the name of a dish in most cases (trademark is a separate matter). So if you consider the names of dishes to be analogous to function names, function names should not fall under copyright in most cases.
That was essentially one of the points made by the District Court. The Appellate Court's response is in the "short phrases" part of the opinion. It basically says: while you can't copyright short phrases, you can copyright a larger corpus made up of short phrases (i.e. the whole API).
