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bors b21a6da340 auto merge of #19870 : mdinger/rust/align_error, r=nick29581
#### Updated 1/12/2014

I updated the multi-line testcase to current but didn't modify the others. The spew code was broke by the `matches!` macro no longer working and I'm not interested in fixing the testcase.

I additionally added one testcase below.

Errors will in general look similar to below if the error is either `mismatched types` or a few other types. The rest are ignored.

---

#### Extra testcase:
```rust
pub trait Foo {
    type A;
    fn boo(&self) -> <Self as Foo>::A;
}

struct Bar;

impl Foo for i32 {
    type A = u32;
    fn boo(&self) -> u32 {
        42
    }
}

fn foo1<I: Foo<A=Bar>>(x: I) {
    let _: Bar = x.boo();
}

fn foo2<I: Foo>(x: I) {
    let _: Bar = x.boo();
}


pub fn baz(x: &Foo<A=Bar>) {
    let _: Bar = x.boo();
}


pub fn main() {
    let a = 42i32;
    foo1(a);
    baz(&a);
}
```

#### Multi-line output:
```cmd
$ ./rustc test3.rs
test3.rs:20:18: 20:25 error: mismatched types:
 expected `Bar`,
    found `<I as Foo>::A`
(expected struct `Bar`,
    found associated type)
test3.rs:20     let _: Bar = x.boo();
                             ^~~~~~~
test3.rs:31:5: 31:9 error: type mismatch resolving `<i32 as Foo>::A == Bar`:
 expected u32,
    found struct `Bar`
test3.rs:31     foo1(a);
                ^~~~
test3.rs:31:5: 31:9 note: required by `foo1`
test3.rs:31     foo1(a);
                ^~~~
test3.rs:32:9: 32:11 error: type mismatch resolving `<i32 as Foo>::A == Bar`:
 expected u32,
    found struct `Bar`
test3.rs:32     baz(&a);
                    ^~
test3.rs:32:9: 32:11 note: required for the cast to the object type `Foo`
test3.rs:32     baz(&a);
                    ^~
error: aborting due to 3 previous errors
```

---

This is a continuation of #19203 which I apparently broke by force pushing after it was closed. I'm attempting to add multi-line errors where they are largely beneficial - to help differentiate different types in compiler messages. As before, this is still a simple fix.

#### Testcase:
```rust
struct S;

fn test() -> Option<i32> {
    let s: S;

    s
}

fn test2() -> Option<i32> {
    Ok(7) // Should be Some(7)
}

impl Iterator for S {
    type Item = i32;
    fn next(&mut self) -> Result<i32, i32> { Ok(7) }
}

fn main(){ 
    test();
    test2();

}
```

---

#### Single-line playpen errors:
```cmd
<anon>:6:5: 6:6 error: mismatched types: expected `core::option::Option<int>`, found `S` (expected enum core::option::Option, found struct S)
<anon>:6     s
             ^
<anon>:10:5: 10:10 error: mismatched types: expected `core::option::Option<int>`, found `core::result::Result<_, _>` (expected enum core::option::Option, found enum core::result::Result)
<anon>:10     Ok(7) // Should be Some(7)
              ^~~~~
<anon>:14:5: 14:55 error: method `next` has an incompatible type for trait: expected enum core::option::Option, found enum core::result::Result [E0053]
<anon>:14     fn next(&mut self) -> Result<uint, uint> { Ok(7) }
              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
error: aborting due to 3 previous errors
playpen: application terminated with error code 101
```

---

#### Multi-line errors:
```cmd
$ ./rustc test.rs
test.rs:6:5: 6:6 error: mismatched types:
 expected `core::option::Option<i32>`,
    found `S`
(expected enum `core::option::Option`,
    found struct `S`)
test.rs:6     s
              ^
test.rs:10:5: 10:10 error: mismatched types:
 expected `core::option::Option<i32>`,
    found `core::result::Result<_, _>`
(expected enum `core::option::Option`,
    found enum `core::result::Result`)
test.rs:10     Ok(7) // Should be Some(7)
               ^~~~~
test.rs:15:5: 15:53 error: method `next` has an incompatible type for trait: expected enum `core::option::Option`, found enum `core::result::Result` [E0053]
test.rs:15     fn next(&mut self) -> Result<i32, i32> { Ok(7) }
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
error: aborting due to 3 previous errors
```

---

#### Positive notes
* Vim worked fine with it: https://github.com/rust-lang/rust/pull/19203#issuecomment-66861668
* `make check` didn't find any errors
* Fixed *backtick* placement suggested by @p1start at https://github.com/rust-lang/rust/pull/19203#issuecomment-64062052

#### Negative notes
* Didn't check Emacs support but also wasn't provided a testcase...
* Needs to be tested with macro errors but I don't have a good testcase yet
* I would like to move the `E[0053]` earlier (see https://github.com/rust-lang/rust/issues/19464#issuecomment-65334301) but I don't know how
* It might be better to indent the types slightly like so (but I don't know how):
```cmd
test.rs:6:5: 6:6 error: mismatched types:
          expected `core::option::Option<int>`,
             found `S`
         (expected enum `core::option::Option`,
             found struct `S`)
test.rs:6     s
```
* Deep whitespace indentation may be a bad idea because early wrapping will cause misalignment between lines

#### Other
* I thought that compiler flags or something else (environment variables maybe) might be required because of comments against it but now that seems too much of a burden for users and for too little gain.
* There was concern that it will make large quantities of errors difficult to distinguish but I don't find that an issue. They both look awful and multi-line errors makes the types easier to understand.

---

#### Single lined spew:
```cmd
$ rustc test2.rs 
test2.rs:161:9: 170:10 error: method `next` has an incompatible type for trait: expected enum core::option::Option, found enum core::result::Result [E0053]
test2.rs:161         fn next(&mut self) -> Result<&'a str, int> {
test2.rs:162             self.curr = self.next;
test2.rs:163             
test2.rs:164             if let (Some(open), Some(close)) = Parens::find_parens(self.all, self.next) {
test2.rs:165                 self.next = if self.all.char_at(self.next) == '(' { close }
test2.rs:166                 else { open }
             ...
test2.rs:164:21: 164:31 error: mismatched types: expected `core::result::Result<uint, int>`, found `core::option::Option<_>` (expected enum core::result::Result, found enum core::option::Option)
test2.rs:164             if let (Some(open), Some(close)) = Parens::find_parens(self.all, self.next) {
                                 ^~~~~~~~~~
test2.rs:164:33: 164:44 error: mismatched types: expected `core::result::Result<uint, int>`, found `core::option::Option<_>` (expected enum core::result::Result, found enum core::option::Option)
test2.rs:164             if let (Some(open), Some(close)) = Parens::find_parens(self.all, self.next) {
                                             ^~~~~~~~~~~
test2.rs:169:40: 169:76 error: mismatched types: expected `core::result::Result<&'a str, int>`, found `core::option::Option<&str>` (expected enum core::result::Result, found enum core::option::Option)
test2.rs:169             if self.curr != self.len { Some(self.all[self.curr..self.next]) } else { None }
                                                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test2.rs:169:86: 169:90 error: mismatched types: expected `core::result::Result<&'a str, int>`, found `core::option::Option<_>` (expected enum core::result::Result, found enum core::option::Option)
test2.rs:169             if self.curr != self.len { Some(self.all[self.curr..self.next]) } else { None }
                                                                                                  ^~~~
test2.rs:205:14: 205:18 error: mismatched types: expected `core::result::Result<uint, int>`, found `core::option::Option<uint>` (expected enum core::result::Result, found enum core::option::Option)
test2.rs:205             (open, close)
                          ^~~~
test2.rs:205:20: 205:25 error: mismatched types: expected `core::result::Result<uint, int>`, found `core::option::Option<uint>` (expected enum core::result::Result, found enum core::option::Option)
test2.rs:205             (open, close)
                                ^~~~~
test2.rs:210:21: 210:31 error: mismatched types: expected `core::result::Result<uint, int>`, found `core::option::Option<_>` (expected enum core::result::Result, found enum core::option::Option)
test2.rs:210             if let (Some(open), _) = Parens::find_parens(self.all, 0) {
                                 ^~~~~~~~~~
test2.rs:210:13: 212:28 error: mismatched types: expected `core::option::Option<&'a int>`, found `core::option::Option<&str>` (expected int, found str)
test2.rs:210             if let (Some(open), _) = Parens::find_parens(self.all, 0) {
test2.rs:211                 Some(self.all[0..open])
test2.rs:212             } else { None }
test2.rs:299:48: 299:58 error: mismatched types: expected `Box<translate::Entity>`, found `collections::vec::Vec<_>` (expected box, found struct collections::vec::Vec)
test2.rs:299         pub fn new() -> Entity { Entity::Group(Vec::new()) }
                                                            ^~~~~~~~~~
test2.rs:359:51: 359:58 error: type `&mut Box<translate::Entity>` does not implement any method in scope named `push`
test2.rs:359                 Entity::Group(ref mut vec) => vec.push(e),
                                                               ^~~~~~~
test2.rs:366:51: 366:85 error: type `&mut Box<translate::Entity>` does not implement any method in scope named `push`
test2.rs:366                 Entity::Group(ref mut vec) => vec.push(Entity::Inner(s.to_string())),
                                                               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
error: aborting due to 12 previous errors
```

---

#### Multi-line spew:

```cmd
$ ./rustc test2.rs 
test2.rs:161:9: 170:10 error: method `next` has an incompatible type for trait:
 expected enum `core::option::Option`,
    found enum `core::result::Result` [E0053]
test2.rs:161         fn next(&mut self) -> Result<&'a str, int> {
test2.rs:162             self.curr = self.next;
test2.rs:163             
test2.rs:164             if let (Some(open), Some(close)) = Parens::find_parens(self.all, self.next) {
test2.rs:165                 self.next = if self.all.char_at(self.next) == '(' { close }
test2.rs:166                 else { open }
             ...
test2.rs:164:21: 164:31 error: mismatched types:
 expected `core::result::Result<uint, int>`,
    found `core::option::Option<_>`
(expected enum `core::result::Result`,
    found enum `core::option::Option`)
test2.rs:164             if let (Some(open), Some(close)) = Parens::find_parens(self.all, self.next) {
                                 ^~~~~~~~~~
test2.rs:164:33: 164:44 error: mismatched types:
 expected `core::result::Result<uint, int>`,
    found `core::option::Option<_>`
(expected enum `core::result::Result`,
    found enum `core::option::Option`)
test2.rs:164             if let (Some(open), Some(close)) = Parens::find_parens(self.all, self.next) {
                                             ^~~~~~~~~~~
test2.rs:169:40: 169:76 error: mismatched types:
 expected `core::result::Result<&'a str, int>`,
    found `core::option::Option<&str>`
(expected enum `core::result::Result`,
    found enum `core::option::Option`)
test2.rs:169             if self.curr != self.len { Some(self.all[self.curr..self.next]) } else { None }
                                                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test2.rs:169:86: 169:90 error: mismatched types:
 expected `core::result::Result<&'a str, int>`,
    found `core::option::Option<_>`
(expected enum `core::result::Result`,
    found enum `core::option::Option`)
test2.rs:169             if self.curr != self.len { Some(self.all[self.curr..self.next]) } else { None }
                                                                                                  ^~~~
test2.rs:205:14: 205:18 error: mismatched types:
 expected `core::result::Result<uint, int>`,
    found `core::option::Option<uint>`
(expected enum `core::result::Result`,
    found enum `core::option::Option`)
test2.rs:205             (open, close)
                          ^~~~
test2.rs:205:20: 205:25 error: mismatched types:
 expected `core::result::Result<uint, int>`,
    found `core::option::Option<uint>`
(expected enum `core::result::Result`,
    found enum `core::option::Option`)
test2.rs:205             (open, close)
                                ^~~~~
test2.rs:210:21: 210:31 error: mismatched types:
 expected `core::result::Result<uint, int>`,
    found `core::option::Option<_>`
(expected enum `core::result::Result`,
    found enum `core::option::Option`)
test2.rs:210             if let (Some(open), _) = Parens::find_parens(self.all, 0) {
                                 ^~~~~~~~~~
test2.rs:210:13: 212:28 error: mismatched types:
 expected `core::option::Option<&'a int>`,
    found `core::option::Option<&str>`
(expected int,
    found str)
test2.rs:210             if let (Some(open), _) = Parens::find_parens(self.all, 0) {
test2.rs:211                 Some(self.all[0..open])
test2.rs:212             } else { None }
test2.rs:229:57: 229:96 error: the trait `core::ops::Fn<(char,), bool>` is not implemented for the type `|char| -> bool`
test2.rs:229                                              .map(|s| s.trim_chars(|c: char| c.is_whitespace()))
                                                                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test2.rs:238:46: 239:75 error: type `core::str::CharSplits<'_, |char| -> bool>` does not implement any method in scope named `filter_map`
test2.rs:238                                             .filter_map(|s| if !s.is_empty() { Some(s.trim_chars('\'')) }
test2.rs:239                                                             else { None })
test2.rs:237:46: 237:91 error: the trait `core::ops::Fn<(char,), bool>` is not implemented for the type `|char| -> bool`
test2.rs:237                 let vec: Vec<&str> = value[].split(|c: char| matches!(c, '(' | ')' | ','))
                                                          ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test2.rs:238:65: 238:77 error: the type of this value must be known in this context
test2.rs:238                                             .filter_map(|s| if !s.is_empty() { Some(s.trim_chars('\'')) }
                                                                             ^~~~~~~~~~~~
test2.rs:299:48: 299:58 error: mismatched types:
 expected `Box<translate::Entity>`,
    found `collections::vec::Vec<_>`
(expected box,
    found struct `collections::vec::Vec`)
test2.rs:299         pub fn new() -> Entity { Entity::Group(Vec::new()) }
                                                            ^~~~~~~~~~
test2.rs:321:36: 322:65 error: type `core::str::CharSplits<'_, |char| -> bool>` does not implement any method in scope named `filter_map`
test2.rs:321                                   .filter_map(|s| if !s.is_empty() { Some(s.trim_chars('\'')) }
test2.rs:322                                                   else { None })
test2.rs:320:36: 320:81 error: the trait `core::ops::Fn<(char,), bool>` is not implemented for the type `|char| -> bool`
test2.rs:320             let vec: Vec<&str> = s.split(|c: char| matches!(c, '(' | ')' | ','))
                                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test2.rs:321:55: 321:67 error: the type of this value must be known in this context
test2.rs:321                                   .filter_map(|s| if !s.is_empty() { Some(s.trim_chars('\'')) }
                                                                   ^~~~~~~~~~~~
test2.rs:359:51: 359:58 error: type `&mut Box<translate::Entity>` does not implement any method in scope named `push`
test2.rs:359                 Entity::Group(ref mut vec) => vec.push(e),
                                                               ^~~~~~~
test2.rs:366:51: 366:85 error: type `&mut Box<translate::Entity>` does not implement any method in scope named `push`
test2.rs:366                 Entity::Group(ref mut vec) => vec.push(Entity::Inner(s.to_string())),
                                                               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
error: aborting due to 24 previous errors
```

Closes #18946 #19464
cc @P1start @jakub- @tomjakubowski @kballard @chris-morgan
2015-01-12 08:55:22 +00:00
man Man page/--help dialog fix 2015-01-03 11:34:01 -08:00
mk auto merge of #20802 : huonw/rust/book-css, r=steveklabnik 2015-01-10 05:55:07 +00:00
src auto merge of #19870 : mdinger/rust/align_error, r=nick29581 2015-01-12 08:55:22 +00:00
.gitattributes webfonts: proper fix 2014-07-08 20:29:36 +02:00
.gitignore gitignore: Add the autogenerated/downloaded unicode data files. 2014-08-03 17:32:53 +10:00
.gitmodules Use rust-installer for installation 2014-12-11 17:14:17 -08:00
.mailmap Update .mailmap 2014-10-23 23:01:31 +02:00
.travis.yml Allow travis to use newer-faster infrastructure for building. http://blog.travis-ci.com/2014-12-17-faster-builds-with-container-based-infrastructure/ 2015-01-01 02:00:29 -05:00
AUTHORS.txt Add new authors, more relnotes 2015-01-06 16:37:38 -08:00
configure "The Rust Programming Language" 2015-01-08 12:02:11 -05:00
CONTRIBUTING.md Put links to discuss.rust-lang.org and #rust-internals in CONTRIBUTING.md 2015-01-02 15:42:38 -08:00
COPYRIGHT Update COPYRIGHT to better reflect the current repo 2014-10-06 10:55:39 -07:00
LICENSE-APACHE Update license, add license boilerplate to most files. Remainder will follow. 2012-12-03 17:12:14 -08:00
LICENSE-MIT Change the licence holder to The Rust Project Developers 2014-05-03 23:59:24 +02:00
Makefile.in Fix incorrect link in Makefile.in documentation 2014-12-28 22:42:12 +01:00
README.md "The Rust Programming Language" 2015-01-08 12:02:11 -05:00
RELEASES.md Link to http://rustbyexample.com/ 2015-01-09 08:25:42 +01:00

The Rust Programming Language

This is a compiler for Rust, including standard libraries, tools and documentation.

Quick Start

  1. Download a binary installer for your platform.
  2. Read The Rust Programming Language.
  3. Enjoy!

Note: Windows users can read the detailed using Rust on Windows notes on the wiki.

Building from Source

  1. Make sure you have installed the dependencies:

    • g++ 4.7 or clang++ 3.x
    • python 2.6 or later (but not 3.x)
    • perl 5.0 or later
    • GNU make 3.81 or later
    • curl
    • git
  2. Download and build Rust:

    You can either download a tarball or build directly from the repo.

    To build from the tarball do:

     $ curl -O https://static.rust-lang.org/dist/rust-nightly.tar.gz
     $ tar -xzf rust-nightly.tar.gz
     $ cd rust-nightly
    

    Or to build from the repo do:

     $ git clone https://github.com/rust-lang/rust.git
     $ cd rust
    

    Now that you have Rust's source code, you can configure and build it:

     $ ./configure
     $ make && make install
    

    Note: You may need to use sudo make install if you do not normally have permission to modify the destination directory. The install locations can be adjusted by passing a --prefix argument to configure. Various other options are also supported, pass --help for more information on them.

    When complete, make install will place several programs into /usr/local/bin: rustc, the Rust compiler, and rustdoc, the API-documentation tool.

  3. Read The Rust Programming Language.

  4. Enjoy!

Building on Windows

To easily build on windows we can use MSYS2:

  1. Grab the latest MSYS2 installer and go through the installer.

  2. Now from the MSYS2 terminal we want to install the mingw64 toolchain and the other tools we need.

     $ pacman -S mingw-w64-i686-toolchain
     $ pacman -S base-devel
    
  3. With that now start mingw32_shell.bat from where you installed MSYS2 (i.e. C:\msys).

  4. From there just navigate to where you have Rust's source code, configure and build it:

     $ ./configure
     $ make && make install
    

Notes

Since the Rust compiler is written in Rust, it must be built by a precompiled "snapshot" version of itself (made in an earlier state of development). As such, source builds require a connection to the Internet, to fetch snapshots, and an OS that can execute the available snapshot binaries.

Snapshot binaries are currently built and tested on several platforms:

  • Windows (7, 8, Server 2008 R2), x86 and x86-64 (64-bit support added in Rust 0.12.0)
  • Linux (2.6.18 or later, various distributions), x86 and x86-64
  • OSX 10.7 (Lion) or greater, x86 and x86-64

You may find that other platforms work, but these are our officially supported build environments that are most likely to work.

Rust currently needs about 1.5 GiB of RAM to build without swapping; if it hits swap, it will take a very long time to build.

There is a lot more documentation in the wiki.

Getting help and getting involved

The Rust community congregates in a few places:

License

Rust is primarily distributed under the terms of both the MIT license and the Apache License (Version 2.0), with portions covered by various BSD-like licenses.

See LICENSE-APACHE, LICENSE-MIT, and COPYRIGHT for details.