This commit revisits the `cast` module in libcore and libstd, and scrutinizes
all functions inside of it. The result was to remove the `cast` module entirely,
folding all functionality into the `mem` module. Specifically, this is the fate
of each function in the `cast` module.
* transmute - This function was moved to `mem`, but it is now marked as
#[unstable]. This is due to planned changes to the `transmute`
function and how it can be invoked (see the #[unstable] comment).
For more information, see RFC 5 and #12898
* transmute_copy - This function was moved to `mem`, with clarification that is
is not an error to invoke it with T/U that are different
sizes, but rather that it is strongly discouraged. This
function is now #[stable]
* forget - This function was moved to `mem` and marked #[stable]
* bump_box_refcount - This function was removed due to the deprecation of
managed boxes as well as its questionable utility.
* transmute_mut - This function was previously deprecated, and removed as part
of this commit.
* transmute_mut_unsafe - This function doesn't serve much of a purpose when it
can be achieved with an `as` in safe code, so it was
removed.
* transmute_lifetime - This function was removed because it is likely a strong
indication that code is incorrect in the first place.
* transmute_mut_lifetime - This function was removed for the same reasons as
`transmute_lifetime`
* copy_lifetime - This function was moved to `mem`, but it is marked
`#[unstable]` now due to the likelihood of being removed in
the future if it is found to not be very useful.
* copy_mut_lifetime - This function was also moved to `mem`, but had the same
treatment as `copy_lifetime`.
* copy_lifetime_vec - This function was removed because it is not used today,
and its existence is not necessary with DST
(copy_lifetime will suffice).
In summary, the cast module was stripped down to these functions, and then the
functions were moved to the `mem` module.
transmute - #[unstable]
transmute_copy - #[stable]
forget - #[stable]
copy_lifetime - #[unstable]
copy_mut_lifetime - #[unstable]
[breaking-change]
These implementations must live in libstd right now because the fmt module has
not been migrated yet. This will occur in a later PR.
Just to be clear, there are new extension traits, but they are not necessary
once the std::fmt module has migrated to libcore, which is a planned migration
in the future.
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]
for `~str`/`~[]`.
Note that `~self` still remains, since I forgot to add support for
`Box<self>` before the snapshot.
How to update your code:
* Instead of `~EXPR`, you should write `box EXPR`.
* Instead of `~TYPE`, you should write `Box<Type>`.
* Instead of `~PATTERN`, you should write `box PATTERN`.
[breaking-change]
This currently requires linking against a library like libquadmath (or
libgcc), because compiler-rt barely has any support for this and most
hardware does not yet have 128-bit precision floating point. For this
reason, it's currently hidden behind a feature gate.
When compiler-rt is updated to trunk, some tests can be added for
constant evaluation since there will be support for the comparison
operators.
Closes#13381
This removes all resizability support for ~[T] vectors in preparation of DST.
The only growable vector remaining is Vec<T>. In summary, the following methods
from ~[T] and various functions were removed. Each method/function has an
equivalent on the Vec type in std::vec unless otherwise stated.
* slice::OwnedCloneableVector
* slice::OwnedEqVector
* slice::append
* slice::append_one
* slice::build (no replacement)
* slice::bytes::push_bytes
* slice::from_elem
* slice::from_fn
* slice::with_capacity
* ~[T].capacity()
* ~[T].clear()
* ~[T].dedup()
* ~[T].extend()
* ~[T].grow()
* ~[T].grow_fn()
* ~[T].grow_set()
* ~[T].insert()
* ~[T].pop()
* ~[T].push()
* ~[T].push_all()
* ~[T].push_all_move()
* ~[T].remove()
* ~[T].reserve()
* ~[T].reserve_additional()
* ~[T].reserve_exect()
* ~[T].retain()
* ~[T].set_len()
* ~[T].shift()
* ~[T].shrink_to_fit()
* ~[T].swap_remove()
* ~[T].truncate()
* ~[T].unshift()
* ~str.clear()
* ~str.set_len()
* ~str.truncate()
Note that no other API changes were made. Existing apis that took or returned
~[T] continue to do so.
[breaking-change]
`Reader`, `Writer`, `MemReader`, `MemWriter`, and `MultiWriter` now work with `Vec<u8>` instead of `~[u8]`. This does introduce some extra copies since `from_utf8_owned` isn't usable anymore, but I think that can't be helped until `~str`'s representation changes.
This is in preparation to remove the implementations of ToStrRadix in integers, and to remove the associated logic from `std::num::strconv`.
The parts that still need to be liberated are:
- `std::fmt::Formatter::runplural`
- `num::{bigint, complex, rational}`
This "bubble up an error" macro was originally named if_ok! in order to get it
landed, but after the fact it was discovered that this name is not exactly
desirable.
The name `if_ok!` isn't immediately clear that is has much to do with error
handling, and it doesn't look fantastic in all contexts (if if_ok!(...) {}). In
general, the agreed opinion about `if_ok!` is that is came in as subpar.
The name `try!` is more invocative of error handling, it's shorter by 2 letters,
and it looks fitting in almost all circumstances. One concern about the word
`try!` is that it's too invocative of exceptions, but the belief is that this
will be overcome with documentation and examples.
Close#12037
* All I/O now returns IoResult<T> = Result<T, IoError>
* All formatting traits now return fmt::Result = IoResult<()>
* The if_ok!() macro was added to libstd
* Reexport io::mem and io::buffered structs directly under io, make mem/buffered
private modules
* Remove with_mem_writer
* Remove DEFAULT_CAPACITY and use DEFAULT_BUF_SIZE (in io::buffered)
cc #11119
* Reexport io::mem and io::buffered structs directly under io, make mem/buffered
private modules
* Remove with_mem_writer
* Remove DEFAULT_CAPACITY and use DEFAULT_BUF_SIZE (in io::buffered)
Unique pointers and vectors currently contain a reference counting
header when containing a managed pointer.
This `{ ref_count, type_desc, prev, next }` header is not necessary and
not a sensible foundation for tracing. It adds needless complexity to
library code and is responsible for breakage in places where the branch
has been left out.
The `borrow_offset` field can now be removed from `TyDesc` along with
the associated handling in the compiler.
Closes#9510Closes#11533
The `print!` and `println!` macros are now the preferred method of printing, and so there is no reason to export the `stdio` functions in the prelude. The functions have also been replaced by their macro counterparts in the tutorial and other documentation so that newcomers don't get confused about what they should be using.
This is just an unnecessary trait that no one's ever going to parameterize over
and it's more useful to just define the methods directly on the types
themselves. The implementors of this type almost always don't want
inner_mut_ref() but they're forced to define it as well.
