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24 lines
965 B
24 lines
965 B
3 years ago
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fn main() {
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let s = String::from("hello"); // s comes into scope
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takes_ownership(s); // s's value moves into the function...
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// ... and so is no longer valid here
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let x = 5; // x comes into scope
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makes_copy(x); // x would move into the function,
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// but i32 is Copy, so it's okay to still
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// use x afterward
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} // Here, x goes out of scope, then s. But because s's value was moved, nothing
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// special happens.
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fn takes_ownership(some_string: String) { // some_string comes into scope
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println!("{}", some_string);
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} // Here, some_string goes out of scope and `drop` is called. The backing
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// memory is freed.
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fn makes_copy(some_integer: i32) { // some_integer comes into scope
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println!("{}", some_integer);
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} // Here, some_integer goes out of scope. Nothing special happens.
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