Where ItemDecorator creates new items given a single item, ItemModifier
alters the tagged item in place. The expansion rules for this are a bit
weird, but I think are the most reasonable option available.
When an item is expanded, all ItemModifier attributes are stripped from
it and the item is folded through all ItemModifiers. At that point, the
process repeats until there are no ItemModifiers in the new item.
This is mostly a reaction to #12730. If we are going to keep calling them `char`, at least make it clear that they aren't characters but codepoint/scalar.
This seems to be causing some confusion among users. Rust's char are
not 8bit characters, but 32bit UCS-4 codepoint without surrogates
(Unicode Scalar Values as per Unicode glossary).
Make the doc more explicit about it.
Signed-off-by: Luca Bruno <lucab@debian.org>
* `Ord` inherits from `Eq`
* `TotalOrd` inherits from `TotalEq`
* `TotalOrd` inherits from `Ord`
* `TotalEq` inherits from `Eq`
This is a partial implementation of #12517.
If no arguments are given to `vec!` then no pushes are emitted and
so the compiler (rightly) complains that the mutability of `temp` is
never used.
This behaviour is rather annoying for users.
When using tasks in Rust, the expectation is that the runtime does not exit
before all tasks have exited. This is enforced in libgreen through the
`SchedPool` type, and it is enforced in libnative through a `bookkeeping` module
and a global count/mutex pair. Unfortunately, this means that a process which
originates with libgreen will not wait for spawned native tasks.
In order to fix this problem, the bookkeeping module was moved from libnative to
libstd so the runtime itself can wait for native tasks to exit. Green tasks do
not manage themselves through this bookkeeping module, but native tasks will
continue to manage themselves through this module.
Closes#12684
Using nanosleep() allows us to gracefully recover from EINTR because on error it
fills in the second parameter with the remaining time to sleep.
Closes#12689
The `std::cmp` functions are not correct for floating point types.
`min(NaN, 2.0)` and `min(2.0, NaN)` return different values, because
these functions assume a total order. Floating point types need special
`min`, `max` and `clamp` functions.
I added a new lint for variables whose names contain uppercase characters, since, by convention, variable names should be all lowercase. What motivated me to work on this was when I ran into something like the following:
```rust
use std::io::File;
use std::io::IoError;
fn main() {
let mut f = File::open(&Path::new("/something.txt"));
let mut buff = [0u8, ..16];
match f.read(buff) {
Ok(cnt) => println!("read this many bytes: {}", cnt),
Err(IoError{ kind: EndOfFile, .. }) => println!("Got end of file: {}", EndOfFile.to_str()),
}
}
```
I then got compile errors when I tried to add a wildcard match pattern at the end which I found very confusing since I believed that the 2nd match arm was only matching the EndOfFile condition. The problem is that I hadn't imported io::EndOfFile into the local scope. So, I thought that I was using EndOfFile as a sub-pattern, however, what I was actually doing was creating a new local variable named EndOfFile. This lint makes this error easier to spot by providing a warning that the variable name EndOfFile contains a uppercase characters which provides a nice hint as to why the code isn't doing what is intended.
The lint warns on local bindings as well:
```rust
let Hi = 0;
```
And also struct fields:
```rust
struct Something {
X: uint
}
```
- Added `TraitObject` representation to `std::raw`.
- Added doc to `std::raw`.
- Removed `Any::as_void_ptr()` and `Any::as_mut_void_ptr()`
methods as they are uneccessary now after the removal of
headers on owned boxes. This reduces the number of virtual calls needed from 2 to 1.
- Made the `..Ext` implementations work directly with the repr of
a trait object.
- Removed `Any`-related traits from the prelude.
- Added bench.
Bench before/after:
~~~
7 ns/iter (+/- 0)
4 ns/iter (+/- 0)
~~~
- Added `TraitObject` representation to `std::raw`.
- Added doc to `std::raw`.
- Removed `Any::as_void_ptr()` and `Any::as_mut_void_ptr()`
methods as they are uneccessary now after the removal of
headers on owned boxes. This reduces the number of virtual calls needed.
- Made the `..Ext` implementations work directly with the repr of
a trait object.
- Removed `Any`-related traits from the prelude.
- Added bench for `Any`
Similarly to #12422 which made stdin buffered by default, this commit makes the
output streams also buffered by default. Now that buffered writers will flush
their contents when they are dropped, I don't believe that there's no reason why
the output shouldn't be buffered by default, which is what you want in 90% of
cases.
As with stdin, there are new stdout_raw() and stderr_raw() functions to get
unbuffered streams to stdout/stderr.
It's still not entirely clear what should happen if there was an error when
flushing, but I'm deferring that decision to #12628. I believe that it's crucial
for the usefulness of buffered writers to be able to flush on drop. It's just
too easy to forget to flush them in small one-off use cases.
cc #12628
Formatting via reflection has been a little questionable for some time now, and
it's a little unfortunate that one of the standard macros will silently use
reflection when you weren't expecting it. This adds small bits of code bloat to
libraries, as well as not always being necessary. In light of this information,
this commit switches assert_eq!() to using {} in the error message instead of
{:?}.
In updating existing code, there were a few error cases that I encountered:
* It's impossible to define Show for [T, ..N]. I think DST will alleviate this
because we can define Show for [T].
* A few types here and there just needed a #[deriving(Show)]
* Type parameters needed a Show bound, I often moved this to `assert!(a == b)`
* `Path` doesn't implement `Show`, so assert_eq!() cannot be used on two paths.
I don't think this is much of a regression though because {:?} on paths looks
awful (it's a byte array).
Concretely speaking, this shaved 10K off a 656K binary. Not a lot, but sometime
significant for smaller binaries.
I've been playing around with code size when linking to libstd recently, and these were some findings I found that really helped code size. I started out by eliminating all I/O implementations from libnative and instead just return an unimplemented error.
In doing so, a `fn main() {}` executable was ~378K before this patch, and about 170K after the patch. These size wins are all pretty minor, but they all seemed pretty reasonable to me. With native I/O not stubbed out, this takes the size of an LTO executable from 675K to 400K.
This function is a tiny wrapper that LLVM doesn't want to inline, and it ends up
causing more bloat than necessary. The bloat is pretty small, but it's a win of
at least 7k for small executables, and I imagine that the number goes up as
there are more calls to fail!().
This removes all usage of Poly in format strings from libstd. This doesn't
prevent more future strings from coming in, but it at least removes the ones for
now.