BloomCatalog class

A localized message catalog storing translated templates for a single BCP-47 locale.

Stores translation message templates indexed by message ID and evaluates them using ICU MessageFormat syntax in pure Dart. Supports variable interpolation, pluralization with # count replacement, select/gender branching, nested sub-patterns, number formatting, and date formatting.

Fully source- and syntax-compatible with server-side packages/bloom_i18n.

Supported ICU MessageFormat Syntax

Variable Interpolation: {name} substitutes args['name'].
Escaped Characters: Two consecutive single quotes '' emit a single quote '. Quoted brace blocks such as '{escaped}' prevent interpolation and emit {escaped}.
Plurals: {count, plural, =0 {No items} =1 {One item} other {# items}}. Exact numeric matches (=0, =1, =2, etc.) take precedence over keyword branches (zero, one, two, other). The # character within a plural branch is automatically replaced by the localized number representation via formatNumber.
Select & Gender: {gender, select, female {She liked} male {He liked} other {They liked}}.
Number Formatting: {amount, number, currency} or {rate, number, percent}.
Date Formatting: {date, date, short}, {date, date, medium}, {date, date, long}, {date, date, full}, or custom token patterns like {date, date, yyyy-MM-dd}.

final catalog = BloomCatalog('en-US', {
  'greeting': 'Hello, {name}!',
  'cart_items': '{count, plural, =0 {Cart is empty} =1 {1 item} other {# items}}',
});

final text = catalog.get('cart_items', args: {'count': 3}); // "3 items"

Constructors

BloomCatalog(String locale, Map<String, String> messages): Creates a BloomCatalog from a map of message IDs to ICU-formatted message templates.
BloomCatalog.fromJson(String locale, Map<String, dynamic> json): Creates a BloomCatalog from a dynamic map, converting values to strings.
factory
BloomCatalog.fromJsonString(String locale, String jsonString): Creates a BloomCatalog by decoding a JSON-encoded string.
factory

Properties

hashCode → int: The hash code for this object.
no setterinherited
locale → String: The BCP-47 language tag identifying the locale of this catalog (e.g. 'en-US', 'fr-FR', 'de').
final
messages → Map<String, String>: Returns an unmodifiable view of all registered message template strings.
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited

Methods

get(String messageId, {Map<String, Object>? args}) → String?: Looks up and evaluates an ICU MessageFormat template by messageId.
has(String messageId) → bool: Returns true if this catalog contains a template defined for messageId.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
toString() → String: A string representation of this object.
inherited

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Static Methods

formatMessage(String template, {Map<String, Object>? args, String? locale}) → String: Evaluates an ICU MessageFormat template string with args for the specified locale.