pub type LPALSOURCE3F = Option<unsafe extern "C" fn(_: u32, _: i32, _: f32, _: f32, _: f32)>;
enum LPALSOURCE3F { None, Some(unsafe extern "C" fn(_: u32, _: i32, _: f32, _: f32, _: f32)), }
No value.
Some value of type T.
T