Hello everyone. I just published a new crate to crates.io and thought I would share it here.
The crate is called num-format. It’s designed to help you generate string representations of numbers, formatted according to international standards. For example, given
1000000usize, it can produce:
- “1,000,000” for US English
- “10,00,000” for Indian English
- “1 000 000” for French French
It comes with a
Locale enum that has been programmatically generated from the Unicode Consortium’s Common Locale Data Repository, which is how macOS and many others get their localization information; so there are literally hundreds of locales to choose from. If you’d like to use a customized formatting policy, you can do do that as well.
In addition to including comprehensive localization features, num-format is also built for speed. Taking inspiration from dtolnay’s fantastic itoa crate, I made sure you can create a formatted
&str representation without any heap allocation (i.e that you can write into a stack-allocate buffer). This is much faster, but it also means that num-format can be used in a
The formatting capabilities of num-format are currently available for all the “integer” types in the standard library (e.g.
NonZeroU16, etc.) as well as types from the num crate (available behind a feature flag).
In the future, I’d like to expand the capabilities of num-format to include support for floating point numbers as well, but this is not yet implemented. If you’d like to help work on this feature, please let me know!