As part of the shift from ~[T] to Vec<T>, recently ~[T] was made
non-growable. However, the FromIterator implementation for ~[T] was left
intact (albeit implemented inefficiently), which basically provided a
loophole to grow a ~[T] despite its non-growable nature. This is a
problem, both for performance reasons and because it encourages APIs to
continue returning ~[T] when they should return Vec<T>. Removing
FromIterator forces these APIs to adopt the correct type.
Furthermore, during today's weekly meeting it was decided that we should
remove all instances of ~[T] from the standard libraries in favor of
Vec<T>. Removing the FromIterator impl makes sense to do as a result.
This commit only includes the removal of the FromIterator impl. The
subsequent commits involve handling all of the breakage that results,
including changing APIs to use Vec<T> instead of ~[T]. The precise API
changes are documented in the subsequent commit messages, but each
commit is not individually marked as a breaking change.
Finally, a new trait FromVec is introduced that provides a mechanism to
convert Vec<T> back into ~[T] if truly necessary. It is a bit awkward to
use by design, and is anticipated that it will be more useful in a
post-DST world to convert to an arbitrary Foo<[T]> smart pointer.
[breaking-change]
This mostly involved frobbing imports between realstd, realcore, and the core
being test. Some of the imports are a little counterintuitive, but it mainly
focuses around libcore's types not implementing Show while libstd's types
implement Show.
The prospects of a generic failure function such as this existing in libcore are
bleak, due to monomorphization not working across the crate boundary, and
allocation into a ~Any is not allowed in libcore.
The argument to expect() is now &str instead of <M: Send + Any>
[breaking-change]
This adds an small of failure to libcore, hamstrung by the fact that std::fmt
hasn't been migrated yet. A few asserts were re-worked to not use std::fmt
features, but these asserts can go back to their original form once std::fmt has
migrated.
The current failure implementation is to just have some symbols exposed by
std::rt::unwind that are linked against by libcore. This is an explicit circular
dependency, unfortunately. This will be officially supported in the future
through compiler support with much nicer failure messages. Additionally, there
are two depended-upon symbols today, but in the future there will only be one
(once std::fmt has migrated).
Coherence requires that libcore's traits be implemented in libcore for ~[T] and
~str (due to them being language defined types). These implementations cannot
live in libcore forever, but for now, until Heap/Box/Uniq is a lang item, these
implementations must reside inside of libcore. While not perfect
implementations, these shouldn't reside in libcore for too long.
With some form of lang item these implementations can be in a proper crate
because the lang item will not be present in libcore.
This moves as much allocation as possible from teh std::str module into
core::str. This includes essentially all non-allocating functionality, mostly
iterators and slicing and such.
This primarily splits the Str trait into only having the as_slice() method,
adding a new StrAllocating trait to std::str which contains the relevant new
allocation methods. This is a breaking change if any of the methods of "trait
Str" were overriden. The old functionality can be restored by implementing both
the Str and StrAllocating traits.
[breaking-change]
This commit adds a new trait, MutableVectorAllocating, which represents
functions on vectors which can allocate.
This is another extension trait to slices which should be removed once a lang
item exists for the ~ allocation.
This implements all traits inside of core::num for all the primitive types,
removing all the functionality from libstd. The std modules reexport all of the
necessary items from the core modules.
This strips out all string-related functionality from the num module. The
inherited functionality is all that will be implemented in libcore (for now).
Primarily, libcore will not implement the Float trait or any string-related
functionality.
It may be possible to migrate string parsing functionality into libcore in the
future, but for now it will remain in libstd.
All functionality in core::num is reexported in std::num.
This commit removes the std::{managed, reference} modules. The modules serve
essentially no purpose, and the only free function removed was `managed::ptr_eq`
which can be achieved by comparing references.
[breaking-change]
This removes the TotalOrd and TotalEq implementation macros, they will be added
later to the numeric modules (where the other comparison implementations live).
This adds a lint mode for detecting unnecessary allocations on the heap. This isn't super fancy, currently it only has two rules
1. For a function's arguments, if you allocate a `[~|@]str` literal, when the type of the argument is a `&str`, emit a warning.
2. For the same case, emit warnings for boxed vectors when slices are required.
After adding the lint, I rampaged through the libraries and removed all the unnecessary allocations I could find.
