c (context)

ttag supports gettext's standard context feature. The same word can have multiple translations, depending on the usage context.

You can use c with any of ttag functions: t, jt, ngettext, gettext.

If provided context is not found in your translations then default will be used.

Usage

import { c } from 'ttag';

c('email').t`Hello ${name}`;
c('email').jt`Hello ${name}`;
c('email').ngettext(msgid`${n} banana`, `${n} bananas`, n);
c('email').gettext('Hello');

Try

https://jsfiddle.net/AlexMost/tqqxut52/3/

Example

For instance, we can have different translations for the same phrase Hello ${ name }. Depending on the context, there may be reasons to translate this phrase differently whether we are on email or on profile page.

import { c, t } from 'ttag';

c('email').t`Hello ${name}`; // email context

c('profile').t`Hello ${name}`; // profile context

t`Hello ${name}`; // default context

.po file (example for Ukrainian translations):

msgid "Hello ${ name }"
msgstr "Привіт ${ name }"

msgctxt "email"
msgid "Hello ${ name }"
msgstr "Вітаємо ${ name }"

msgctxt "profile"
msgid "Hello ${ name }"
msgstr "Здоровенькі були ${ name }"

Format

The c function only accepts a string identifying the context. Any other value will result in an error

Valid

c('email').t`Hello ${name}`;
c('email').jt`Hello ${name}`;
c('email').ngettext(msgid`${n} banana`, `${n} bananas`, n);
c('email').gettext('Hello');

Invalid

c(fn()).t`Hello ${name}`;
c().t`Hello ${name}`;
c(111).t`Hello ${name}`;

In this case ttag will throw Exception in debug mode (NODE_ENV !== 'production')

Extract

All translations can be extracted to .po file with ttag-cli tool.

import { c, t } from 'ttag';

c('email').t`Hello ${name}`; // email context

will be extracted to this:

msgctxt "email"
msgid "Hello ${ name }"
msgstr ""

Resolve

Suppose we have translated phrase in .po:

msgctxt "email"
msgid "Hello ${ name }"
msgstr "Вітаємо ${ name }"

The result js for uk locale will be

t`Вітаємо ${ name }`.

As you can see, the appropriate translation phrase is on it's place and all context calls are stripped.