I ran `arc lint -- support/xhpast/ast.hpp` in rPHU and was shown a warning for `support/xhpast/astnode.hpp`:
```
> arc lint -- support/xhpast/ast.hpp
>>> Lint for support/xhpast/astnode.hpp:
Warning (Cppcheck) noExplicitConstructor
Class 'Node' has a constructor with 1 argument that is not explicit.
40 l_tok(-1),
41 r_tok(-1) {}
42
>>> 43 Node(unsigned int type) :
44 type(type),
45 l_tok(-1),
46 r_tok(-1) {}
```