0.3.1

Release Notes

User-facing library changes

Here are the most notable changes:

New thresholds for inverses and conversions (#69):

• The inverse_as family now safeguards conversions whose factor is
  less than 1,000,000, instead of 1,000. So for example,
  inverse_as(hertz, milli(seconds)(5)) won't compile anymore without
  an explicit Rep; you would need micro(seconds) or smaller. This
  makes inversion fully lossless for integral values up to 1,000! As
  always, this doesn't affect floating point Rep; these are always
  permitted.

• We slightly loosened the overflow safety surface to permit signed
  32-bit integer conversions with a factor of 1,000,000. For example,
  mega(hertz)(1u).as(hertz) has always worked, but
  mega(hertz)(1).as(hertz) previously didn't. Now it does.

Improve QuantityMaker and SingularNameFor composition (#72):

• It is now possible to compose units such as hertz, whose singular
  name is identical to its plural name. Compositions generally should
  be much easier overall. The downside is that we now permit
  grammatically incorrect combinations, such as (meters / seconds)
  rather than (meters / second), but making that an error was probably
  too heavy handed anyway.

Easy compatibility with nholthaus units:

• In #112, we added a file which users can add to their project, to set
  up a correspondence between types in the nholthaus/units library, and
  Au. This means you can pass an Au quantity to an API expecting an
  equivalent nholthaus type, and vice versa! Formal documentation is
  still pending (see #107 to follow along). However, interested users
  can read the comments in the files added in #112 to see how to set it
  up.

Here are the remaining library changes:

• Bugfix (#98): inverse_as<Rep>(...) did not have the correct Rep.
• Bugfix (#100): QuantityPoint conversion could change Rep for small
  integral types.
• Bugfix (#119): Make default Quantity and QuantityPoint
  constructors noexcept, enabling std::atomic usage on gcc-9.

New units

• fathoms
• furlongs
• knots
• nautical_miles

Thanks to Randall Munroe for supplying the use case:
https://xkcd.com/2585/

Additionally, we added support for these new SI prefixes:

• quetta
• ronna
• ronto
• quecto

Tooling updates

• Added buildifier 5.1.0.
• Upgraded bazel to 6.0.0.
• Tools that wrap bazel commands now give a (transient) message
  explaining why they're slow on the first execution.
• bazel test now shows output for failed tests by default.
• We now compile with -Wextra. (Its absence was an oversight.)
• Warnings are treated as errors, but only in CI (to facilitate
  test-driven development).

Documentation updates

This was a major release for the documentation website. We added the
following pages:

• Development Setup
• Troubleshooting Guide
• Comparison of Alternatives
• Tutorials
  • Au 101: Quantity Makers
  • Au 102: API Types
  • Au 103: Unit Conversions
• Reference Docs

Additionally, we made the following changes:

• Doc website now gets updated automatically on every push to main.
• Main landing page and README have public facing content, not
  placeholders.

Repo updates

• Added Apache 2.0 license.
• Added security policy.
• Enabled automatic enforcement for:
  • copyright headers
  • buildifier linting
  • SHA-pinned GitHub actions (for security)
• Upgraded bazelisk to 1.16.0, fixing deprecation warning.

Closed Issues

Here are all of the issues that were closed between these releases.
(Note that the resolution is at the level of days, so some of these
issues might show up in the notes for more than one release.)

https://github.com/aurora-opensource/au/issues?q=is%3Aissue+closed%3A2022-12-20..2023-03-18

Contributors

Thanks to those who authored or reviewed PRs, or filed or participated
in Issues! Alphabetically:

• @avrahamshukron
• @chiphogg
• @geoffviola
• @johnzoppina
• @kbwilliams17
• @mweeksaurora
• @nkiraly
• @philsc
• @timhirsh
• @tobin