@messageformat/convert

Converts hiearachical objects into [messageformat]-compatible JSON. More
specifically, it:

- Detects two-letter locale keys and parses their contents according to that
locale's pluralisation rules
- Converts #{var} and %{var} variable replacements into their messageformat
equivalents, while properly escaping other {} characters.
- Detects objects encoding pluralisation choices (using the locale-specific set
of CLDR categories, i.e. zero|one|two|few|many|aother) and converts them to
their messageformat equivalents.

With these conversions, messages stored according to the Rails i18n spec may be
used together with [messageformat].

This package was previously named messageformat-convert.

$3

``sh
npm install @messageformat/convert
`

If using in an environment that does not natively support ES6 features such as
object destructuring and arrow functions, you'll want to use a transpiler for this.

$3

`js
const convert = require('@messageformat/convert');
const { locales, translations } = convert({
en: {
format: '%{attribute} %{message}',
errors: {
confirmation: "doesn't match %{attribute}",
accepted: 'must be accepted',
wrong_length: {
one: 'is the wrong length (should be 1 character)',
other: 'is the wrong length (should be %{count} characters)'
},
equal_to: 'must be equal to %{count}'
}
}
});

const MessageFormat = require('@messageformat/core');
const mf = new MessageFormat(locales);
const messages = mf.compile(translations);

messages.en.errors.accepted();
// 'must be accepted'

messages.en.format({
attribute: 'Problem',
message: messages.en.errors.confirmation({ attribute: 'your style' })
});
// 'Problem doesn\'t match your style'

messages.en.errors.wrong_length({ count: 42 });
// 'is the wrong length (should be 42 characters)'
`

$3

data should be a hierarchical object of strings; options is an optional set
of configuration:

- defaultLocale (string, default 'en') – Sets the initial locale.

- includeLocales (array of strings, default null) – By default any key in the
input data that matches the two-letter code of a [CLDR pluralisation language]
switches the language used for determining the pluralisation rules. Set this to
some limited set of languages (or even an empty array) to limit that.

- verbose (boolean, default false) – If set to true, some logging and
warnings will be printed to the console.

For more options, take a look at the source.

The object returned by the function contains the following fields:

- locales (array of strings) – The actual locales encountered in the data

- translations` (object) – An object containing the MessageFormat strings,
matching the shape of the input data

[cldr pluralisation language]: http://www.unicode.org/cldr/charts/latest/supplemental/language_plural_rules.html
[messageformat]: https://messageformat.github.io/

---

Messageformat is an OpenJS Foundation project, and we follow its Code of Conduct.