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[refs]

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refs/tags/0.10: ac33f2b15782272ae348dbd7b14b8257b2148b5a
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refs/tags/0.11.0: e1247cb1d0d681be034adb4b558b5a0c0d5720f9
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refs/tags/0.12.0: f0c419429ef30723ceaf6b42f9b5a2aeb5d2e2d1
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refs/heads/beta: a1f64c2204687263ca1230f08af1cc7317cc4a26
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refs/heads/beta: dbbcb434b12da3465037ff2bbd16b1060afa3469
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refs/tags/1.0.0-alpha: e42bd6d93a1d3433c486200587f8f9e12590a4d7
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refs/heads/tmp: 370fe2786109360f7c35b8ba552b83b773dd71d6
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refs/tags/1.0.0-alpha.2: 4c705f6bc559886632d3871b04f58aab093bfa2f

branches/beta/src/doc/trpl/functions.md

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@@ -214,11 +214,61 @@ fn diverges() -> ! {
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`panic!` is a macro, similar to `println!()` that we’ve already seen. Unlike
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`println!()`, `panic!()` causes the current thread of execution to crash with
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the given message.
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the given message. Because this function will cause a crash, it will never
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return, and so it has the type ‘`!`’, which is read ‘diverges’.
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Because this function will cause a crash, it will never return, and so it has
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the type ‘`!`’, which is read ‘diverges’. A diverging function can be used
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as any type:
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If you add a main function that calls `diverges()` and run it, you’ll get
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some output that looks like this:
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```text
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thread ‘<main>’ panicked at ‘This function never returns!’, hello.rs:2
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```
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If you want more information, you can get a backtrace by setting the
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`RUST_BACKTRACE` environment variable:
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```text
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$ RUST_BACKTRACE=1 ./diverges
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thread '<main>' panicked at 'This function never returns!', hello.rs:2
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stack backtrace:
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1: 0x7f402773a829 - sys::backtrace::write::h0942de78b6c02817K8r
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2: 0x7f402773d7fc - panicking::on_panic::h3f23f9d0b5f4c91bu9w
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3: 0x7f402773960e - rt::unwind::begin_unwind_inner::h2844b8c5e81e79558Bw
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4: 0x7f4027738893 - rt::unwind::begin_unwind::h4375279447423903650
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5: 0x7f4027738809 - diverges::h2266b4c4b850236beaa
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6: 0x7f40277389e5 - main::h19bb1149c2f00ecfBaa
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7: 0x7f402773f514 - rt::unwind::try::try_fn::h13186883479104382231
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8: 0x7f402773d1d8 - __rust_try
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9: 0x7f402773f201 - rt::lang_start::ha172a3ce74bb453aK5w
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10: 0x7f4027738a19 - main
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11: 0x7f402694ab44 - __libc_start_main
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12: 0x7f40277386c8 - <unknown>
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13: 0x0 - <unknown>
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```
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`RUST_BACKTRACE` also works with Cargo’s `run` command:
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```text
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$ RUST_BACKTRACE=1 cargo run
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Running `target/debug/diverges`
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thread '<main>' panicked at 'This function never returns!', hello.rs:2
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stack backtrace:
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1: 0x7f402773a829 - sys::backtrace::write::h0942de78b6c02817K8r
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2: 0x7f402773d7fc - panicking::on_panic::h3f23f9d0b5f4c91bu9w
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3: 0x7f402773960e - rt::unwind::begin_unwind_inner::h2844b8c5e81e79558Bw
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4: 0x7f4027738893 - rt::unwind::begin_unwind::h4375279447423903650
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5: 0x7f4027738809 - diverges::h2266b4c4b850236beaa
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6: 0x7f40277389e5 - main::h19bb1149c2f00ecfBaa
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7: 0x7f402773f514 - rt::unwind::try::try_fn::h13186883479104382231
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8: 0x7f402773d1d8 - __rust_try
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9: 0x7f402773f201 - rt::lang_start::ha172a3ce74bb453aK5w
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10: 0x7f4027738a19 - main
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11: 0x7f402694ab44 - __libc_start_main
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12: 0x7f40277386c8 - <unknown>
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13: 0x0 - <unknown>
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```
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A diverging function can be used as any type:
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```should_panic
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# fn diverges() -> ! {

branches/beta/src/doc/trpl/trait-objects.md

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// y.method();
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(y.vtable.method)(y.data);
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```
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## Object Safety
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Not every trait can be used to make a trait object. For example, vectors implement
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`Clone`, but if we try to make a trait object:
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```ignore
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let v = vec![1, 2, 3];
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let o = &v as &Clone;
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```
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We get an error:
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```text
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error: cannot convert to a trait object because trait `core::clone::Clone` is not object-safe [E0038]
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let o = &v as &Clone;
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^~
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note: the trait cannot require that `Self : Sized`
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let o = &v as &Clone;
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^~
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```
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The error says that `Clone` is not ‘object-safe’. Only traits that are
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object-safe can be made into trait objects. A trait is object-safe if both of
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these are true:
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* the trait does not require that `Self: Sized`
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* all of its methods are object-safe
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So what makes a method object-safe? Each method must require that `Self: Sized`
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or all of the following:
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* must not have any type parameters
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* must not use `Self`
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Whew! As we can see, almost all of these rules talk about `Self`. A good intuition
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is “except in special circumstances, if your trait’s method uses `Self`, it is not
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object-safe.”

branches/beta/src/libcollections/binary_heap.rs

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//! // 7
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//! // +-----------------+
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//! // | |
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//! // v 1 2 | 2
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//! // v 1 2 |
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//! // 0 -----> 1 -----> 3 ---> 4
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//! // | ^ ^ ^
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//! // | | 1 | |

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