Each formatting trait now has an example of implementation, as well as a
fuller description of what it's supposed to output.
It also contains a link to the module-level documentation which
Fixes#25765
This commit shards the broad `core` feature of the libcore library into finer
grained features. This split groups together similar APIs and enables tracking
each API separately, giving a better sense of where each feature is within the
stabilization process.
A few minor APIs were deprecated along the way:
* Iterator::reverse_in_place
* marker::NoCopy
This commit removes all the old casting/generic traits from `std::num` that are
no longer in use by the standard library. This additionally removes the old
`strconv` module which has not seen much use in quite a long time. All generic
functionality has been supplanted with traits in the `num` crate and the
`strconv` module is supplanted with the [rust-strconv crate][rust-strconv].
[rust-strconv]: https://github.com/lifthrasiir/rust-strconv
This is a breaking change due to the removal of these deprecated crates, and the
alternative crates are listed above.
[breaking-change]
Fixes#20596 by making `Debug` render negative zero with a `-` without affecting the behavior of `Display`.
While I was at it, I also removed some dead code from `float_to_str_bytes_common` (the one from `libcore/fmt/float.rs`, not the function of the same name in `libstd/num/strconv.rs`). It had support for different bases, and for negative numbers, but the function is internal to core and the couple places that call it (all in `libcore/fmt/mod.rs`) never use those features: They pass in `num.abs()` and base 10.
Arguments, Formatters, and the various format traits remain stable. The
format_args! macro uses #[allow_internal_unstable] to allow it access to
the unstable things in core::fmt.
Destabilized things include a "v1" in their name:
* core::fmt::rt
* core::fmt::rt::v1 (the module and all contents)
* core::fmt::ArgumentV1
* core::fmt::ArgumentV1::new
* core::fmt::ArgumentV1::from_usize
* core::fmt::Arguments::new_v1
* core::fmt::Arguments::new_v1_formatted
The unstable message was copied from that of std::io::_print.
This fixes the bug described in issue #23150. This affected formatting any floating point number into a string in a formatting pattern that: a) required rounding up, and b) required an extra digit on the front.
So `format!("{:.0}", 9.9)` would fail, but `format!("{:.0}", 8.9)` would succeed. This was due to a negative integer being cast to a `usize` resulting in an 'arithmetic operation overflowed' panic.
The fix was to change the order of operations so that the number is zero before casting.
This commit stabilizes the `std::num` module:
* The `Int` and `Float` traits are deprecated in favor of (1) the
newly-added inherent methods and (2) the generic traits available in
rust-lang/num.
* The `Zero` and `One` traits are reintroduced in `std::num`, which
together with various other traits allow you to recover the most
common forms of generic programming.
* The `FromStrRadix` trait, and associated free function, is deprecated
in favor of inherent implementations.
* A wide range of methods and constants for both integers and floating
point numbers are now `#[stable]`, having been adjusted for integer
guidelines.
* `is_positive` and `is_negative` are renamed to `is_sign_positive` and
`is_sign_negative`, in order to address #22985
* The `Wrapping` type is moved to `std::num` and stabilized;
`WrappingOps` is deprecated in favor of inherent methods on the
integer types, and direct implementation of operations on
`Wrapping<X>` for each concrete integer type `X`.
Closes#22985Closes#21069
[breaking-change]
r? @alexcrichton
This commit stabilizes the `std::num` module:
* The `Int` and `Float` traits are deprecated in favor of (1) the
newly-added inherent methods and (2) the generic traits available in
rust-lang/num.
* The `Zero` and `One` traits are reintroduced in `std::num`, which
together with various other traits allow you to recover the most
common forms of generic programming.
* The `FromStrRadix` trait, and associated free function, is deprecated
in favor of inherent implementations.
* A wide range of methods and constants for both integers and floating
point numbers are now `#[stable]`, having been adjusted for integer
guidelines.
* `is_positive` and `is_negative` are renamed to `is_sign_positive` and
`is_sign_negative`, in order to address #22985
* The `Wrapping` type is moved to `std::num` and stabilized;
`WrappingOps` is deprecated in favor of inherent methods on the
integer types, and direct implementation of operations on
`Wrapping<X>` for each concrete integer type `X`.
Closes#22985Closes#21069
[breaking-change]
This functions swaps the order of arguments to a few functions that previously
took (output, input) parameters, but now take (input, output) parameters (in
that order).
The affected functions are:
* ptr::copy
* ptr::copy_nonoverlapping
* slice::bytes::copy_memory
* intrinsics::copy
* intrinsics::copy_nonoverlapping
Closes#22890
[breaking-change]
The collections debug helpers no longer prefix output with the
collection name, in line with the current conventions for Debug
implementations. Implementations that want to preserve the current
behavior can simply add a `try!(write!(fmt, "TypeName "));` at the
beginning of the `fmt` method.
[breaking-change]
The collections debug helpers no longer prefix output with the
collection name, in line with the current conventions for Debug
implementations. Implementations that want to preserve the current
behavior can simply add a `try!(write!(fmt, "TypeName "));` at the
beginning of the `fmt` method.
[breaking-change]
