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Move explanation up as per @aturon

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Steve Klabnik 2016-08-25 16:32:36 -04:00 committed by Carol (Nichols || Goulding)
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commit 730fb1f82f
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12
src/ch07-02-unrecoverable-errors-with-panic.md
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@ -39,7 +39,12 @@ fn main() {
``` ```
We attempt to access the hundredth element of our vector, but it only has three We attempt to access the hundredth element of our vector, but it only has three
elements. In this situation, Rust will panic. Let's try it: elements. In this situation, Rust will panic. Using `[]` is supposed to return
a number. But if you pass it an invalid index, there's no number Rust could
return here, it would be wrong. So the only thing that we can do is terminate
the program.
Let's try to run it:
```bash ```bash
$ cargo run $ cargo run
@ -97,8 +102,3 @@ error: Process didn't exit successfully: `target/debug/panic` (exit code: 101)
That's a lot of output! Line `11` there has the line in our project: That's a lot of output! Line `11` there has the line in our project:
`src/main.rs` line four. `src/main.rs` line four.
So why does Rust panic here? In this case, using `[]` is supposed to return
a number. But if you pass it an invalid index, there's no number Rust could
return here, it would be wrong. So the only thing that we can do is terminate
the program.