According to #7887, we've decided to use the syntax of `fn map<U>(f: &fn(&T) -> U) -> U`, which passes a reference to the closure, and to `fn map_move<U>(f: &fn(T) -> U) -> U` which moves the value into the closure. This PR adds these `.map_move()` functions to `Option` and `Result`.
In addition, it has these other minor features:
* Replaces a couple uses of `option.get()`, `result.get()`, and `result.get_err()` with `option.unwrap()`, `result.unwrap()`, and `result.unwrap_err()`. (See #8268 and #8288 for a more thorough adaptation of this functionality.
* Removes `option.take_map()` and `option.take_map_default()`. These two functions can be easily written as `.take().map_move(...)`.
* Adds a better error message to `result.unwrap()` and `result.unwrap_err()`.
The two deletions are because the test cases are very old (still using `class` and modes!), and, as far as I can tell (since they are so old), the areas they test are well tested by other rpass tests.
Some general clean-up relating to deriving:
- `TotalOrd` was too eager, and evaluated the `.cmp` call for every field, even if it could short-circuit earlier.
- the pointer types didn't have impls for `TotalOrd` or `TotalEq`.
- the Makefiles didn't reach deep enough into libsyntax for dependencies.
(Split out from https://github.com/mozilla/rust/pull/8258.)
FromHex ignores whitespace and parses either upper or lower case hex
digits. ToHex outputs lower case hex digits with no whitespace. Unlike
ToBase64, ToHex doesn't allow you to configure the output format. I
don't feel that it's super useful in this case.
This results in throwing away alias analysis information, because LLVM
does *not* implement reasoning about these conversions yet.
We specialize zero-size types since a `getelementptr` offset will
return us the same pointer, making it broken as a simple counter.
This module provided adaptors for the old internal iterator protocol,
but they proved to be quite unreadable and are not generic enough to
handle borrowed pointers well.
Since Rust no longer defines an internal iteration protocol, I don't
think there's going to be any reuse via these adaptors.
This lazily initializes the taskgroup structs for ```spawn_unlinked``` tasks. If such a task never spawns another task linked to it (or a descendant of it), its taskgroup is simply never initialized at all. Also if an unlinked task spawns another unlinked task, neither of them will need to initialize their taskgroups. This works for the main task too.
I benchmarked this with the following test case and observed a ~~21% speedup (average over 4 runs: 7.85 sec -> 6.20 sec, 2.5 GHz)~~ 11% speedup, see comment below.
```
use std::task;
use std::cell::Cell;
use std::rt::comm;
static NUM: uint = 1024*256;
fn run(f: ~fn()) {
let mut t = task::task();
t.unlinked();
t.spawn(f);
}
fn main() {
do NUM.times {
let (p,c) = comm::oneshot();
let c = Cell::new(c);
do run { c.take().send(()); }
p.recv();
}
}
```