Pluralization

@logosdx/localize supports ICU-lite plural syntax using Intl.PluralRules for locale-aware category selection. This means pluralization rules are determined by the runtime, not hardcoded — so languages with complex plural forms (Arabic, Polish, Welsh) work correctly out of the box.

• ICU-lite Syntax
• Supported Categories
• Multi-language Examples
• parsePlural() Standalone Helper
• Mixing Plurals with Variables

ICU-lite Syntax

The syntax is {varName, plural, category {template}} where # is replaced with the numeric value.

const labels = {
    cart: {
        items: '{count, plural, one {# item} other {# items}} in your cart',
        reviews: '{count, plural, zero {No reviews yet} one {# review} other {# reviews}}'
    }
};

i18n.t('cart.items', { count: 0 });
// "0 items in your cart"

i18n.t('cart.items', { count: 1 });
// "1 item in your cart"

i18n.t('cart.items', { count: 12 });
// "12 items in your cart"

i18n.t('cart.reviews', { count: 0 });
// "No reviews yet"

Supported Categories

Categories are resolved by Intl.PluralRules based on the current locale. English uses one and other, but languages like Arabic, Polish, or Welsh use additional categories.

Category	When Used	Example Languages
zero	Explicit zero (if defined)	Arabic, Latvian
one	Singular (locale-dependent)	English, Spanish, French
two	Dual forms	Arabic, Welsh
few	Small quantities	Polish, Czech, Russian
many	Large quantities	Polish, Russian, Arabic
other	Default fallback (always required)	All languages

WARNING

The other category is required in every plural expression. It serves as the fallback when no other category matches.

Multi-language Examples

// English — uses 'one' and 'other'
const en = {
    notifications: '{count, plural, one {# notification} other {# notifications}}'
};

// Polish — uses 'one', 'few', 'many', and 'other'
const pl = {
    notifications: '{count, plural, one {# powiadomienie} few {# powiadomienia} many {# powiadomień} other {# powiadomień}}'
};

// Arabic — uses 'zero', 'one', 'two', 'few', 'many', 'other'
const ar = {
    notifications: '{count, plural, zero {لا إشعارات} one {إشعار واحد} two {إشعاران} few {# إشعارات} many {# إشعارًا} other {# إشعار}}'
};

parsePlural() Standalone Helper

The parsePlural function is exported separately for use outside of LocaleManager. It resolves plural syntax in a string given a set of values and a locale code.

import { parsePlural } from '@logosdx/localize';

parsePlural(
    '{count, plural, one {# item} other {# items}}',
    { count: 5 },
    'en'
);
// "5 items"

parsePlural(
    'You have {count, plural, one {# message} other {# messages}}',
    { count: 1 },
    'en'
);
// "You have 1 message"

TIP

parsePlural only handles the plural syntax. Variable substitution ({name} placeholders) is handled separately by the format helper. When using t() on the manager, both steps happen automatically.

Mixing Plurals with Variables

Plural expressions and regular variables can coexist in the same template string.

const labels = {
    order: {
        summary: '{customer} ordered {count, plural, one {# item} other {# items}} totaling {total}'
    }
};

i18n.t('order.summary', { customer: 'Elena', count: 3, total: '$149.97' });
// "Elena ordered 3 items totaling $149.97"