Dates, numbers and text

Required

• Take the currency from the amount and not from the locale

  LOC-27

  Format every price with the currency code stored with that amount. The reader's locale chooses only the separators and the symbol position.

• Change the case of identifiers without a locale

  LOC-29

  Lower-case and upper-case keys, protocol words, file extensions and identifiers with locale-independent functions. Use locale-aware case only for text shown to people.

Recommended

• Format dates and numbers for the reader

  LOC-11

  Format dates, numbers and money for the reader's locale with a formatting library. Show times with a named time zone.

• Read the week start and units from locale data

  LOC-28

  Read the first day of the week, the weekend, the 12 or 24 hour clock and the measurement system from CLDR locale data. Never hard-code them.

• Sort and compare text by locale

  LOC-15

  Sort and compare visible text with a collator for the reader's locale, and normalise Unicode before comparing or storing it.

• Accept names and addresses from every country

  LOC-16

  Let people enter names and addresses as they are written in their country. Never reject letters, word counts or field shapes your own country does not use.

Avoid

• Writing date formats by hand

  LOC-26

  Never build a date for people from a hand-written pattern such as MM/dd/yyyy. Ask the formatter for a style or a skeleton, and let the locale data order the fields.