Swift FormatStyle Use Foundation's type-safe APIs for user-facing display and when the same convention must accept input. Route String Catalogs, plurals, localized copy, bundles, and RTL layout to ; formatting still requires locale review even when no text is translated. Contents - Workflow - Quick Reference - Selection and Availability - Parsing - SwiftUI Integration - Custom FormatStyle - Common Mistakes - Review Checklist - References Workflow 1. Identify the value's semantic type and whether output is display-only or must round-trip through parsing. 2. Select the narrowest built-in style…