src/librustc_error_codes/error_codes/E0040.md

   1 It is not allowed to manually call destructors in Rust.
   2
   3 Erroneous code example:
   4
   5 ```compile_fail,E0040
   6 struct Foo {
   7     x: i32,
   8 }
   9
  10 impl Drop for Foo {
  11     fn drop(&mut self) {
  12         println!("kaboom");
  13     }
  14 }
  15
  16 fn main() {
  17     let mut x = Foo { x: -7 };
  18     x.drop(); // error: explicit use of destructor method
  19 }
  20 ```
  21
  22 It is unnecessary to do this since `drop` is called automatically whenever a
  23 value goes out of scope. However, if you really need to drop a value by hand,
  24 you can use the `std::mem::drop` function:
  25
  26 ```
  27 struct Foo {
  28     x: i32,
  29 }
  30 impl Drop for Foo {
  31     fn drop(&mut self) {
  32         println!("kaboom");
  33     }
  34 }
  35 fn main() {
  36     let mut x = Foo { x: -7 };
  37     drop(x); // ok!
  38 }
  39 ```