indexTranslations function

String Function(String key, String expanded) indexTranslations(String catalog)

The wrapper for one catalog — hand it to whatever seam the project's translations expose.

widget = TranslationOverride(wrapper: indexTranslations('app'), child: app);

The signature is String Function(String key, String value) because that is what a catalog's own hook already looks like wherever one exists. What comes back is == the value and renders identically; it is simply a distinct object, which is what lets a capture name the key.

Cached per catalog, so repeated calls hand back the same closure. An InheritedWidget carrying this will compare wrappers in updateShouldNotify, and a fresh closure per build would notify every dependent on every rebuild.

Implementation

String Function(String key, String value) indexTranslations(String catalog) =>
    TranslationIndex._wrappers[catalog] ??= (key, value) =>
        TranslationIndex.record(catalog, key, value);