@thestinger and I talked about this in IRC. There are a couple of use
cases for a persistent map, but they aren't common enough to justify
inclusion in libextra and vary enough that they would require multiple
implementations anyways.
In any case, fun_treemap in its current state is basically useless.
I need `Clone` for `Tm` for my latest work on [rust-http](https://github.com/chris-morgan/rust-http) (static typing for headers, and headers like `Date` are a time), so here it is.
@huonw recommended deriving DeepClone while I was at it.
I also had to implement `DeepClone` for `~str` to get a derived implementation of `DeepClone` for `Tm`; I did `@str` while I was at it, for consistency.
An MD5 implementation was originally included in #8097, but, since there are a couple different implementations of that digest algorithm (@alco mentioned his implementation on the mailing list just before I opened that PR), it was suggested that I remove it from that PR and open up a new PR to discuss the different implementations and the best way forward. If anyone wants to discuss a different implementation, feel free to present it here and discuss and compare it to this one. I'll just discuss my implementation and I'll leave it to others to present details of theirs.
This implementation relies on the FixedBuffer struct from cryptoutil.rs for managing the input buffer, just like the Sha1 and Sha2 digest implementations do. I tried manually unrolling the loops in the compression function, but I got slightly worse performance when I did that.
Outside of the #[test]s, I also tested the implementation by generating 1,000 inputs of up to 10MB in size and checking the MD5 digest calculated by this code against the MD5 digest calculated by Java's implementation.
On my computer, I'm getting the following performance:
```
test md5::bench::md5_10 ... bench: 52 ns/iter (+/- 1) = 192 MB/s
test md5::bench::md5_1k ... bench: 2819 ns/iter (+/- 44) = 363 MB/s
test md5::bench::md5_64k ... bench: 178566 ns/iter (+/- 4927) = 367 MB/s
```
Addresses part of #7104
This module adds the ability to generate UUIDs (on all Rust-supported platforms).
I reviewed the existing UUID support in libraries for a range of languages; Go, D, C#, Java and Boost++. The features were all very similar, and this patch essentially covers the union. The implmentation is quite straightforward, and uses the underlying rng support which is assumed to be sufficiently strong for this purpose.
This patch is not complete, however I have put this up for review to gather feedback before finalising. It has tests for most features and documentation for most functions.
Outstanding issues:
* Only generates V4 (Random) UUIDs. Do we want to support the SHA-1 hash based flavour as well?
* Is it worth having the field-based struct public as well as the byte array?
* Formatting the string with '-' between groups not done yet.
* Parsing full string not done as there appears to be no regexp support yet. I can write a simple manual parser for now?
* D has a generator as well. This would be easy to add. However, given the simple interface for creating a new one, and the presence of the macro, is this useful?
* Is it worth having a separate UUID trait and specific implementation? Or should it just have a struct+impl with the same name? Currently it feels weird to have the trait (which can't be named UUID so as to conflict) a separate thing.
* Should the macro be visible at the top level scope?
As this is a first attempt, some code may not be idiomatic. Please comment below...
Thanks for all feedback!
The shift_add_check_overflow and shift_add_check_overflow_tuple functions are
re-written to be more efficient and to make use of the CheckedAdd instrinsic
instead of manually checking for integer overflow.
* The invokation leading_zeros() is removed and replaced with simple integer
comparison. The leading_zeros() method results in a ctpop LLVM instruction
and it may not be efficient on all architectures; integer comparisons,
however, are efficient on just about any architecture.
* The methods lose the ability for the caller to specify a particular shift
value - that functionality wasn't being used and removing it allows for the
code to be simplified.
* Finally, the methods are renamed to add_bytes_to_bits and
add_bytes_to_bits_tuple to reflect their very specific purposes.
- generate random UUIDs
- convert to and from strings and bytes
- parse common string formats
- implements Zero, Clone, FromStr, ToStr, Eq, TotalEq and Rand
- unit tests and documentation
- parsing error codes and strings
- incorporate feedback from PR review
If they are on the trait then it is extremely annoying to use them as
generic parameters to a function, e.g. with the iterator param on the trait
itself, if one was to pass an Extendable<int> to a function that filled it
either from a Range or a Map<VecIterator>, one needs to write something
like:
fn foo<E: Extendable<int, Range<int>> +
Extendable<int, Map<&'self int, int, VecIterator<int>>>
(e: &mut E, ...) { ... }
since using a generic, i.e. `foo<E: Extendable<int, I>, I: Iterator<int>>`
means that `foo` takes 2 type parameters, and the caller has to specify them
(which doesn't work anyway, as they'll mismatch with the iterators used in
`foo` itself).
This patch changes it to:
fn foo<E: Extendable<int>>(e: &mut E, ...) { ... }
.with_c_str() is a replacement for the old .as_c_str(), to avoid
unnecessary boilerplate.
Replace all usages of .to_c_str().with_ref() with .with_c_str().
If they are on the trait then it is extremely annoying to use them as
generic parameters to a function, e.g. with the iterator param on the trait
itself, if one was to pass an Extendable<int> to a function that filled it
either from a Range or a Map<VecIterator>, one needs to write something
like:
fn foo<E: Extendable<int, Range<int>> +
Extendable<int, Map<&'self int, int, VecIterator<int>>>
(e: &mut E, ...) { ... }
since using a generic, i.e. `foo<E: Extendable<int, I>, I: Iterator<int>>`
means that `foo` takes 2 type parameters, and the caller has to specify them
(which doesn't work anyway, as they'll mismatch with the iterators used in
`foo` itself).
This patch changes it to:
fn foo<E: Extendable<int>>(e: &mut E, ...) { ... }
Use Eq + Ord for lexicographical ordering of sequences.
For each of <, <=, >= or > as R, use::
[x, ..xs] R [y, ..ys] = if x != y { x R y } else { xs R ys }
Previous code using `a < b` and then `!(b < a)` for short-circuiting
fails on cases such as [1.0, 2.0] < [0.0/0.0, 3.0], where the first
element was effectively considered equal.
Containers like &[T] did also implement only one comparison operator `<`,
and derived the comparison results from this. This isn't correct either for
Ord.
Implement functions in `std::iterator::order::{lt,le,gt,ge,equal,cmp}` that all
iterable containers can use for lexical order.
We also visit tuple ordering, having the same problem and same solution
(but differing implementation).
I'm a bit disappointed that I couldn't figure out how to factor out more of the code implementing `extra::sync` but I feel this is an okay start. Also I added some documentation explaining that `WaitQueue` isn't thread safe, and needs an exclusive lock.
@bblum
This PR fixes#7235 and #3371, which removes trailing nulls from `str` types. Instead, it replaces the creation of c strings with a new type, `std::c_str::CString`, which wraps a malloced byte array, and respects:
* No interior nulls
* Ends with a trailing null
Basically, generic containers should not use the default methods since a
type of elements may not guarantees total order. str could use them
since u8's Ord guarantees total order. Floating point numbers are also
broken with the default methods because of NaN. Thanks for @thestinger.
Timespec also guarantees total order AIUI. I'm unsure whether
extra::semver::Identifier does so I left it alone. Proof needed.
Signed-off-by: OGINO Masanori <masanori.ogino@gmail.com>
This is a fairly large rollup, but I've tested everything locally, and none of
it should be platform-specific.
r=alexcrichton (bdfdbdd)
r=brson (d803c18)
r=alexcrichton (a5041d0)
r=bstrie (317412a)
r=alexcrichton (135c85e)
r=thestinger (8805baa)
r=pcwalton (0661178)
r=cmr (9397fe0)
r=cmr (caa4135)
r=cmr (6a21d93)
r=cmr (4dc3379)
r=cmr (0aa5154)
r=cmr (18be261)
r=thestinger (f10be03)
Write external iterators for Difference, Sym. Difference, Intersection
and Union set operations.
These iterators are generic insofar that they could work on any ordered
sequence iterators, even though they are type specialized to the
TreeSetIterator in this case.
Looking at the `check` function in the treeset tests, rustc seems
unwilling to compile a function resembling::
fn check<'a, T: Iterator<&'a int>>(... )
so the tests for these iterators are still running the legacy loop
protocol.
