Plurals and formatting: numbers, dates, Measurement
Plurals
English has two forms (one, other), Russian four categories (one: 1, 21, 101; few: 2–4, 22–24; many: 5–20, 25–30; other: fractions), Arabic six. So count == 1 ? "file" : "files" is already wrong for Russian "2 файла" and "21 файл".
The right way is one string with a number and plural variations in the String Catalog:
// In the catalog, the key "%lld files" gets the forms:
// en: one "%lld file", other "%lld files"
let text = String(localized: "\(count) files")The number's type in the interpolation matters: Int gives %lld, and the variations are bound to it.
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