pub type VipsRegionFillFn = Option<unsafe extern "C" fn(arg1: *mut _VipsRegion, arg2: *mut c_void) -> c_int>;
pub enum VipsRegionFillFn { None, Some(unsafe extern "C" fn(*mut _VipsRegion, *mut c_void) -> i32), }
No value.
Some value of type T.
T