You are reading the documentation right. I wasn't here when the syntax was codified, but my understanding is the following. For parameter types our hands were t

You are reading the documentation right. I wasn't here when the syntax was codified, but my understanding is the following. For parameter types our hands were tied, since PHP actually already has this syntax for object types (unless we wanted to needlessly break compatibility here). We just extended it with primitive types, generics, etc. For return types, we wanted to preserve the greppability of "function add" in large codebases, both for the actual "grep" tool itself as well as for any other tools like ctags that look for strings like this.