// TypeError 9553: (140-143): Invalid type for argument in function call. Invalid implicit conversion from function () to function () external requested. Special functions can not be converted to function types.
// TypeError 9553: (230-233): Invalid type for argument in function call. Invalid implicit conversion from function () to function () external requested. Special functions can not be converted to function types.
// TypeError 9553: (345-348): Invalid type for argument in function call. Invalid implicit conversion from function D.f() to function () external requested. Special functions can not be converted to function types.