rust/library/core/src/fmt/float.rs, branch 1.89.0

float: Add `f16` parsing and printing

2025-05-18T16:43:13+00:00

Use the existing Lemire (decimal -> float) and Dragon / Grisu algorithms (float -> decimal) to add support for `f16`. This allows updating the implementation for `Display` to the expected behavior for `Display` (currently it prints the a hex bitwise representation), matching other floats, and adds a `FromStr` implementation. In order to avoid crashes when compiling with Cranelift or on targets where f16 is not well supported, a fallback is used if `cfg(target_has_reliable_f16)` is not true.

Reduce FormattingOptions to 64 bits.

2025-03-12T15:32:00+00:00

Limit formatting width and precision to 16 bits.

2025-03-10T11:20:05+00:00

Access members of `FormattingOptions` directly instead of via getters/setters

2024-12-05T20:48:36+00:00

Formatter: Access members via getter methods wherever possible

2024-12-05T20:47:13+00:00

The idea behind this is to make implementing `fmt::FormattingOptions` (as well as any future changes to `std::Formatter`) easier. In theory, this might have a negative performance impact because of the additional function calls. However, I strongly believe that those will be inlined anyway, thereby producing assembly code that has comparable performance.

remove no-longer-needed abs_private

2024-11-12T06:47:26+00:00

Refactor `floating` macro and nofloat panic message

2024-10-15T13:27:06+00:00

Reformat `use` declarations.

2024-07-28T22:26:52+00:00

The previous commit updated `rustfmt.toml` appropriately. This commit is the outcome of running `x fmt --all` with the new formatting options.

Replace `MaybeUninit::uninit_array()` with array repeat expression.

2024-06-24T17:23:50+00:00

This is possible now that inline const blocks are stable; the idea was even mentioned as an alternative when `uninit_array()` was added: > if it’s stabilized soon enough maybe it’s not worth having a > standard library method that will be replaceable with > `let buffer = [MaybeUninit::::uninit(); $N];` Const array repetition and inline const blocks are now stable (in the next release), so that circumstance has come to pass, and we no longer have reason to want `uninit_array()` other than convenience. Therefore, let’s evaluate the inconvenience by not using `uninit_array()` in the standard library, before potentially deleting it entirely.

Add a `Debug` impl and some basic functions to `f16` and `f128`

2024-04-11T19:31:10+00:00

`compiler_builtins` uses some convenience functions like `is_nan` and `is_sign_positive`. Add these, as well as a temporary implementation for `Debug` that prints the bit representation.