| //! Closure type (equivalent to `&mut dyn FnMut(A) -> R`) that's `repr(C)`. |
| |
| #[repr(C)] |
| pub struct Closure<'a, A, R> { |
| call: unsafe extern "C" fn(&mut Env, A) -> R, |
| env: &'a mut Env, |
| } |
| |
| extern "C" { |
| type Env; |
| } |
| |
| impl<'a, A, R> !Sync for Closure<'a, A, R> {} |
| impl<'a, A, R> !Send for Closure<'a, A, R> {} |
| |
| impl<'a, A, R, F: FnMut(A) -> R> From<&'a mut F> for Closure<'a, A, R> { |
| fn from(f: &'a mut F) -> Self { |
| unsafe extern "C" fn call<A, R, F: FnMut(A) -> R>(env: &mut Env, arg: A) -> R { |
| (*(env as *mut _ as *mut F))(arg) |
| } |
| Closure { call: call::<A, R, F>, env: unsafe { &mut *(f as *mut _ as *mut Env) } } |
| } |
| } |
| |
| impl<'a, A, R> Closure<'a, A, R> { |
| pub fn call(&mut self, arg: A) -> R { |
| unsafe { (self.call)(self.env, arg) } |
| } |
| } |