rollup merge of #19714: steveklabnik/gh16219
These should be properly annotated instead. Fixes #16219.
This commit is contained in:
Brian Anderson
commit
42f4d636fa
@ -37,7 +37,7 @@ It's also helpful to provide the exact version and host by copying the output of
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re-running the erroneous rustc command with the `--version=verbose` flag, which will
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produce something like this:
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```{ignore}
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```text
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rustc 0.12.0 (ba4081a5a 2014-10-07 13:44:41 -0700)
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binary: rustc
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commit-hash: ba4081a5a8573875fed17545846f6f6902c8ba8d
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@ -452,7 +452,7 @@ fn main() {
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Rust will give us a compile-time error:
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```{notrust}
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```text
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Compiling phrases v0.0.1 (file:///home/you/projects/phrases)
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/home/you/projects/phrases/src/main.rs:4:5: 4:40 error: a value named `hello` has already been imported in this module
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/home/you/projects/phrases/src/main.rs:4 use phrases::japanese::greetings::hello;
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@ -76,7 +76,7 @@ fn main() {
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This will give us an error:
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```{notrust}
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```text
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error: non-exhaustive patterns: `_` not covered [E0004]
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```
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@ -189,7 +189,7 @@ panic!("boom");
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gives
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```{notrust}
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```text
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task '<main>' panicked at 'boom', hello.rs:2
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```
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@ -130,7 +130,7 @@ fn add_one(mut num: Box<int>) {
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This does not compile, and gives us an error:
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```{notrust}
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```text
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error: use of moved value: `x`
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println!("{}", x);
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^
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@ -406,7 +406,7 @@ fn main() {
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We try to make four `Wheel`s, each with a `Car` that it's attached to. But the
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compiler knows that on the second iteration of the loop, there's a problem:
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```{notrust}
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```text
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error: use of moved value: `car`
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Wheel { size: 360, owner: car };
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^~~
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@ -84,7 +84,7 @@ println!("{}", x + z);
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This gives us an error:
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```{notrust}
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```text
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hello.rs:6:24: 6:25 error: mismatched types: expected `int` but found `&int` (expected int but found &-ptr)
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hello.rs:6 println!("{}", x + z);
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^
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@ -132,7 +132,7 @@ Pointers are useful in languages that are pass-by-value, rather than
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pass-by-reference. Basically, languages can make two choices (this is made
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up syntax, it's not Rust):
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```{ignore}
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```text
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func foo(x) {
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x = 5
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}
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@ -152,7 +152,7 @@ and therefore, can change its value. At the comment, `i` will be `5`.
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So what do pointers have to do with this? Well, since pointers point to a
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location in memory...
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```{ignore}
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```text
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func foo(&int x) {
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*x = 5
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}
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@ -191,7 +191,7 @@ knows. This might be harmless, and it might be catastrophic.
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When you combine pointers and functions, it's easy to accidentally invalidate
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the memory the pointer is pointing to. For example:
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```{ignore}
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```text
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func make_pointer(): &int {
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x = 5;
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@ -213,7 +213,7 @@ As one last example of a big problem with pointers, **aliasing** can be an
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issue. Two pointers are said to alias when they point at the same location
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in memory. Like this:
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```{ignore}
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```text
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func mutate(&int i, int j) {
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*i = j;
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}
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@ -398,7 +398,7 @@ fn main() {
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It gives this error:
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```{notrust}
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```text
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test.rs:5:8: 5:10 error: cannot assign to `*x` because it is borrowed
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test.rs:5 *x -= 1;
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^~
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@ -522,7 +522,7 @@ boxes, though. As a rough approximation, you can treat this Rust code:
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As being similar to this C code:
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```{ignore}
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```c
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{
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int *x;
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x = (int *)malloc(sizeof(int));
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@ -626,7 +626,7 @@ fn main() {
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This prints:
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```{ignore}
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```text
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Cons(1, box Cons(2, box Cons(3, box Nil)))
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```
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112
src/doc/guide.md
112
src/doc/guide.md
@ -22,7 +22,7 @@ install Rust, but the easiest is to use the `rustup` script. If you're on
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Linux or a Mac, all you need to do is this (note that you don't need to type
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in the `$`s, they just indicate the start of each command):
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```{ignore}
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```bash
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$ curl -s https://static.rust-lang.org/rustup.sh | sudo sh
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```
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@ -39,7 +39,7 @@ If you decide you don't want Rust anymore, we'll be a bit sad, but that's okay.
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Not every programming language is great for everyone. Just pass an argument to
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the script:
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```{ignore}
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```bash
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$ curl -s https://static.rust-lang.org/rustup.sh | sudo sh -s -- --uninstall
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```
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@ -78,13 +78,13 @@ commit is tested against Windows just like any other platform.
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If you've got Rust installed, you can open up a shell, and type this:
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```{ignore}
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```bash
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$ rustc --version
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```
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You should see some output that looks something like this:
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```{ignore}
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```bash
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rustc 0.12.0-nightly (b7aa03a3c 2014-09-28 11:38:01 +0000)
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```
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@ -310,7 +310,7 @@ Make sure to get this name right: you need the capital `C`!
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Put this inside:
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```{ignore}
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```toml
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[package]
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name = "hello_world"
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@ -355,7 +355,7 @@ just `cargo build` and it'll work the right way.
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You'll also notice that Cargo has created a new file: `Cargo.lock`.
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```{ignore}
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```toml
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[root]
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name = "hello_world"
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version = "0.0.1"
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@ -426,7 +426,7 @@ x = 10i;
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It will give you this error:
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```{notrust}
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```text
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error: re-assignment of immutable variable `x`
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x = 10i;
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^~~~~~~
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@ -461,7 +461,7 @@ let x;
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...we'll get an error:
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```{ignore}
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```text
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src/main.rs:2:9: 2:10 error: cannot determine a type for this local variable: unconstrained type
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src/main.rs:2 let x;
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^
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@ -486,7 +486,7 @@ fn main() {
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You can use `cargo build` on the command line to build it. You'll get a warning,
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but it will still print "Hello, world!":
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```{notrust}
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```text
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Compiling hello_world v0.0.1 (file:///home/you/projects/hello_world)
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src/main.rs:2:9: 2:10 warning: unused variable: `x`, #[warn(unused_variable)] on by default
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src/main.rs:2 let x: int;
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@ -664,7 +664,7 @@ let y: int = if x == 5i { 10i; } else { 15i; };
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Note the semicolons after the 10 and 15. Rust will give us the following error:
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```{notrust}
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```text
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error: mismatched types: expected `int` but found `()` (expected int but found ())
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```
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@ -747,7 +747,7 @@ fn print_number(x, y) {
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You get this error:
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```{notrust}
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```text
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hello.rs:5:18: 5:19 error: expected `:` but found `,`
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hello.rs:5 fn print_number(x, y) {
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```
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@ -779,7 +779,7 @@ fn add_one(x: int) -> int {
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We would get an error:
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```{ignore}
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```text
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error: not all control paths return a value
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fn add_one(x: int) -> int {
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x + 1;
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@ -1246,7 +1246,7 @@ So what's the big advantage here? Well, there are a few. First of all, `match`
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enforces 'exhaustiveness checking.' Do you see that last arm, the one with the
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underscore (`_`)? If we remove that arm, Rust will give us an error:
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```{notrust}
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```text
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error: non-exhaustive patterns: `_` not covered
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```
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@ -1864,7 +1864,7 @@ since we're making a binary, rather than a library.
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Check out the generated `Cargo.toml`:
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```{ignore}
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```toml
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[package]
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name = "guessing_game"
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@ -1898,7 +1898,7 @@ Before we move on, let me show you one more Cargo command: `run`. `cargo run`
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is kind of like `cargo build`, but it also then runs the produced executable.
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Try it out:
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```{notrust}
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```bash
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$ cargo run
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Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
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Running `target/guessing_game`
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@ -1996,7 +1996,7 @@ for this example, it is not important.
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Let's try to compile this using `cargo build`:
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```{notrust}
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```bash
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$ cargo build
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Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
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src/main.rs:7:26: 7:34 error: the type of this value must be known in this context
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@ -2044,7 +2044,7 @@ fn main() {
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Try running our new program a few times:
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```{notrust}
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```bash
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$ cargo run
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Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
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Running `target/guessing_game`
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@ -2097,7 +2097,7 @@ fn main() {
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And trying it out:
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```{notrust}
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```bash
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$ cargo run
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Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
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Running `target/guessing_game`
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@ -2152,7 +2152,7 @@ fn cmp(a: int, b: int) -> Ordering {
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If we try to compile, we'll get some errors:
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```{notrust}
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```bash
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$ cargo build
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Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
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src/main.rs:20:15: 20:20 error: mismatched types: expected `int` but found `collections::string::String` (expected int but found struct collections::string::String)
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@ -2206,7 +2206,7 @@ fn cmp(a: uint, b: uint) -> Ordering {
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And try compiling again:
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```{notrust}
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```bash
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$ cargo build
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||||
Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
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||||
src/main.rs:20:15: 20:20 error: mismatched types: expected `uint` but found `collections::string::String` (expected uint but found struct collections::string::String)
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@ -2219,7 +2219,7 @@ This error is similar to the last one: we expected to get a `uint`, but we got
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a `String` instead! That's because our `input` variable is coming from the
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standard input, and you can guess anything. Try it:
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|
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```{notrust}
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```bash
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$ ./target/guessing_game
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Guess the number!
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The secret number is: 73
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@ -2303,7 +2303,7 @@ fn cmp(a: uint, b: uint) -> Ordering {
|
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|
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Let's try it out!
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||||
|
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```{notrust}
|
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```bash
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$ cargo build
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||||
Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
|
||||
src/main.rs:22:15: 22:24 error: mismatched types: expected `uint` but found `core::option::Option<uint>` (expected uint but found enum core::option::Option)
|
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@ -2362,7 +2362,7 @@ fn cmp(a: uint, b: uint) -> Ordering {
|
||||
We use a `match` to either give us the `uint` inside of the `Option`, or we
|
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print an error message and return. Let's give this a shot:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo run
|
||||
Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
|
||||
Running `target/guessing_game`
|
||||
@ -2427,7 +2427,7 @@ fn cmp(a: uint, b: uint) -> Ordering {
|
||||
|
||||
Let's try it!
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo run
|
||||
Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
|
||||
Running `target/guessing_game`
|
||||
@ -2504,7 +2504,7 @@ fn cmp(a: uint, b: uint) -> Ordering {
|
||||
And try it out. But wait, didn't we just add an infinite loop? Yup. Remember
|
||||
that `return`? If we give a non-number answer, we'll `return` and quit. Observe:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo run
|
||||
Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
|
||||
Running `target/guessing_game`
|
||||
@ -2636,7 +2636,7 @@ fn cmp(a: uint, b: uint) -> Ordering {
|
||||
|
||||
Now we should be good! Let's try:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo run
|
||||
Compiling guessing_game v0.0.1 (file:///home/you/projects/guessing_game)
|
||||
Running `target/guessing_game`
|
||||
@ -2814,7 +2814,7 @@ mod hello {
|
||||
|
||||
It gives an error:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
Compiling modules v0.0.1 (file:///home/you/projects/modules)
|
||||
src/main.rs:2:5: 2:23 error: function `print_hello` is private
|
||||
src/main.rs:2 hello::print_hello();
|
||||
@ -2838,7 +2838,7 @@ mod hello {
|
||||
Usage of the `pub` keyword is sometimes called 'exporting', because
|
||||
we're making the function available for other modules. This will work:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo run
|
||||
Compiling modules v0.0.1 (file:///home/you/projects/modules)
|
||||
Running `target/modules`
|
||||
@ -2972,7 +2972,7 @@ $ cd testing
|
||||
|
||||
And try it out:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo run
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
Running `target/testing`
|
||||
@ -3004,7 +3004,7 @@ you give them descriptive names. You'll see why in a moment. We then use a
|
||||
macro, `assert!`, to assert that something is true. In this case, we're giving
|
||||
it `false`, so this test should fail. Let's try it!
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
/home/you/projects/testing/src/main.rs:1:1: 3:2 warning: function is never used: `main`, #[warn(dead_code)] on by default
|
||||
@ -3033,7 +3033,7 @@ task '<main>' failed at 'Some tests failed', /home/you/src/rust/src/libtest/lib.
|
||||
|
||||
Lots of output! Let's break this down:
|
||||
|
||||
```{ignore}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
```
|
||||
@ -3041,7 +3041,7 @@ $ cargo test
|
||||
You can run all of your tests with `cargo test`. This runs both your tests in
|
||||
`tests`, as well as the tests you put inside of your crate.
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
/home/you/projects/testing/src/main.rs:1:1: 3:2 warning: function is never used: `main`, #[warn(dead_code)] on by default
|
||||
/home/you/projects/testing/src/main.rs:1 fn main() {
|
||||
/home/you/projects/testing/src/main.rs:2 println!("Hello, world!")
|
||||
@ -3055,7 +3055,7 @@ case, Rust is warning us that we've written some code that's never used: our
|
||||
We'll turn this lint off for just this function soon. For now, just ignore this
|
||||
output.
|
||||
|
||||
```{ignore}
|
||||
```text
|
||||
Running target/lib-654ce120f310a3a5
|
||||
|
||||
running 1 test
|
||||
@ -3067,7 +3067,7 @@ with good names? This is why. Here, it says 'test foo' because we called our
|
||||
test 'foo.' If we had given it a good name, it'd be more clear which test
|
||||
failed, especially as we accumulate more tests.
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
failures:
|
||||
|
||||
---- foo stdout ----
|
||||
@ -3098,7 +3098,7 @@ fn foo() {
|
||||
|
||||
And then try to run our tests again:
|
||||
|
||||
```{ignore}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
Running target/lib-654ce120f310a3a5
|
||||
@ -3138,7 +3138,7 @@ include `main` when it's _not_ true. So we use `not` to negate things:
|
||||
With this attribute we won't get the warning (even
|
||||
though `src/main.rs` gets recompiled this time):
|
||||
|
||||
```{ignore}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
Running target/lib-654ce120f310a3a5
|
||||
@ -3169,7 +3169,7 @@ fn math_checks_out() {
|
||||
|
||||
And try to run the test:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
/home/you/projects/testing/tests/lib.rs:3:18: 3:38 error: unresolved name `add_three_times_four`.
|
||||
@ -3229,7 +3229,7 @@ fn math_checks_out() {
|
||||
|
||||
Let's give it a run:
|
||||
|
||||
```{ignore}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
Running target/lib-654ce120f310a3a5
|
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@ -3278,7 +3278,7 @@ fn times_four(x: int) -> int { x * 4 }
|
||||
|
||||
If you run `cargo test`, you should get the same output:
|
||||
|
||||
```{ignore}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
Running target/lib-654ce120f310a3a5
|
||||
@ -3332,7 +3332,7 @@ fn test_add_three() {
|
||||
|
||||
We'd get this error:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
/home/you/projects/testing/tests/lib.rs:3:5: 3:24 error: function `add_three` is private
|
||||
/home/you/projects/testing/tests/lib.rs:3 use testing::add_three;
|
||||
@ -3374,7 +3374,7 @@ mod test {
|
||||
|
||||
Let's give it a shot:
|
||||
|
||||
```{ignore}
|
||||
```bash
|
||||
$ cargo test
|
||||
Compiling testing v0.0.1 (file:///home/you/projects/testing)
|
||||
Running target/lib-654ce120f310a3a5
|
||||
@ -3504,7 +3504,7 @@ let y = &mut x;
|
||||
|
||||
Rust will complain:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: cannot borrow immutable local variable `x` as mutable
|
||||
let y = &mut x;
|
||||
^
|
||||
@ -3531,7 +3531,7 @@ let z = &mut x;
|
||||
|
||||
It gives us this error:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: cannot borrow `x` as mutable more than once at a time
|
||||
let z = &mut x;
|
||||
^
|
||||
@ -3677,7 +3677,7 @@ let z = &mut x;
|
||||
|
||||
The error:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: cannot borrow `x` as mutable more than once at a time
|
||||
let z = &mut x;
|
||||
^
|
||||
@ -3695,7 +3695,7 @@ note: previous borrow ends here
|
||||
|
||||
This error comes in three parts. Let's go over each in turn.
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: cannot borrow `x` as mutable more than once at a time
|
||||
let z = &mut x;
|
||||
^
|
||||
@ -3704,7 +3704,7 @@ error: cannot borrow `x` as mutable more than once at a time
|
||||
This error states the restriction: you cannot lend out something mutable more
|
||||
than once at the same time. The borrow checker knows the rules!
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
note: previous borrow of `x` occurs here; the mutable borrow prevents subsequent moves, borrows, or modification of `x` until the borrow ends
|
||||
let y = &mut x;
|
||||
^
|
||||
@ -3716,7 +3716,7 @@ the first mutable borrow occurred. The error showed us the second. So now we
|
||||
see both parts of the problem. It also alludes to rule #3, by reminding us that
|
||||
we can't change `x` until the borrow is over.
|
||||
|
||||
```{ignore}
|
||||
```text
|
||||
note: previous borrow ends here
|
||||
fn main() {
|
||||
let mut x = 5i;
|
||||
@ -3819,7 +3819,7 @@ let y = &mut x;
|
||||
|
||||
This gives us this error:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: cannot use `*x` because it was mutably borrowed
|
||||
*x;
|
||||
^~
|
||||
@ -4624,7 +4624,7 @@ element reference has the closure it's been given as an argument called on it.
|
||||
So this would give us the numbers from `2-100`. Well, almost! If you
|
||||
compile the example, you'll get a warning:
|
||||
|
||||
```{ignore}
|
||||
```text
|
||||
warning: unused result which must be used: iterator adaptors are lazy and
|
||||
do nothing unless consumed, #[warn(unused_must_use)] on by default
|
||||
range(1i, 100i).map(|x| x + 1i);
|
||||
@ -4654,7 +4654,7 @@ for i in std::iter::count(1i, 5i).take(5) {
|
||||
|
||||
This will print
|
||||
|
||||
```{ignore}
|
||||
```text
|
||||
1
|
||||
6
|
||||
11
|
||||
@ -4867,7 +4867,7 @@ We can then use `T` inside the rest of the signature: `x` has type `T`, and half
|
||||
of the `Result` has type `T`. However, if we try to compile that example, we'll get
|
||||
an error:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: binary operation `==` cannot be applied to type `T`
|
||||
```
|
||||
|
||||
@ -4923,7 +4923,7 @@ we use `impl Trait for Item`, rather than just `impl Item`.
|
||||
So what's the big deal? Remember the error we were getting with our generic
|
||||
`inverse` function?
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: binary operation `==` cannot be applied to type `T`
|
||||
```
|
||||
|
||||
@ -4938,7 +4938,7 @@ fn print_area<T>(shape: T) {
|
||||
|
||||
Rust complains:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: type `T` does not implement any method in scope named `area`
|
||||
```
|
||||
|
||||
@ -5014,7 +5014,7 @@ fn main() {
|
||||
|
||||
This program outputs:
|
||||
|
||||
```{ignore}
|
||||
```text
|
||||
This shape has an area of 3.141593
|
||||
This shape has an area of 1
|
||||
```
|
||||
@ -5028,7 +5028,7 @@ print_area(5i);
|
||||
|
||||
We get a compile-time error:
|
||||
|
||||
```{ignore}
|
||||
```text
|
||||
error: failed to find an implementation of trait main::HasArea for int
|
||||
```
|
||||
|
||||
@ -5095,7 +5095,7 @@ fn main() {
|
||||
Now that we've moved the structs and traits into their own module, we get an
|
||||
error:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
error: type `shapes::Circle` does not implement any method in scope named `area`
|
||||
```
|
||||
|
||||
|
||||
@ -313,7 +313,7 @@ print `"Hello"`, or does Rust crash?
|
||||
|
||||
Neither. It refuses to compile:
|
||||
|
||||
```{notrust}
|
||||
```bash
|
||||
$ cargo run
|
||||
Compiling hello_world v0.0.1 (file:///Users/you/src/hello_world)
|
||||
main.rs:8:5: 8:6 error: cannot borrow `v` as mutable because it is also borrowed as immutable
|
||||
@ -431,7 +431,7 @@ fn main() {
|
||||
|
||||
It gives us this error:
|
||||
|
||||
```{notrust}
|
||||
```text
|
||||
6:71 error: capture of moved value: `numbers`
|
||||
for j in range(0, 3) { numbers[j] += 1 }
|
||||
^~~~~~~
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user