Number format to parts

[rxaviers]

Context

Formatter is designed to provide an opaque string as an output that is not meant to be manipulated by the consumer, which makes impossible for UX/design using rich formatting, e.g., "1 000.<strong>35</strong>" and "35.4 <strong>%</strong>".

Goal

Expose format to parts similarly to Ecma-402 Intl.DateTimeFormat.prototype.formatToParts().

References

• https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/DateTimeFormat/formatToParts
• Extend Formatters to allow for token formatting tc39/ecma402#30
• https://tc39.github.io/ecma402/#sec-Intl.DateTimeFormat.prototype.formatToParts