I found a corner case.

```d
interface X {
    void foo()in{}out{}
    body bar();   // <--
}
class C : X { void foo()in{}body{} }
void main() {
    auto c = new C();
    c.foo();
}
```

In the code, 'body' should be parsed as the return type of `bar`. So, you should lookahead one more token and should check it is `TOKlcurly`.