src/doc/book/listings/ch04-understanding-ownership/listing-04-03/src/main.rs

   1 fn main() {
   2     let s = String::from("hello");  // s comes into scope
   3
   4     takes_ownership(s);             // s's value moves into the function...
   5                                     // ... and so is no longer valid here
   6
   7     let x = 5;                      // x comes into scope
   8
   9     makes_copy(x);                  // x would move into the function,
  10                                     // but i32 is Copy, so it's okay to still
  11                                     // use x afterward
  12
  13 } // Here, x goes out of scope, then s. But because s's value was moved, nothing
  14   // special happens.
  15
  16 fn takes_ownership(some_string: String) { // some_string comes into scope
  17     println!("{}", some_string);
  18 } // Here, some_string goes out of scope and `drop` is called. The backing
  19   // memory is freed.
  20
  21 fn makes_copy(some_integer: i32) { // some_integer comes into scope
  22     println!("{}", some_integer);
  23 } // Here, some_integer goes out of scope. Nothing special happens.