Sprinter

Validates format strings and argument types at runtime, throwing descriptive FormatString.Error for mismatches, which prevents crashes and memory corruption common with Swift's native formatter.

Supports standard IEEE printf tokens like %s for C strings and Apple's Objective-C extensions, enabling cross-platform string code that Swift's String(format:) cannot handle, as highlighted in the README's examples.

Includes an optional locale parameter for formatting numbers and punctuation according to different regions, demonstrated with examples for en-US, fr-FR, and de-DE locales in the README.

FormatString instances are stateless and can be cached and reused across threads safely, improving performance by avoiding repeated parsing and formatter initialization, as noted in the thread safety and advanced usage sections.

Exposes the types property to inspect required argument types, useful for building validation tools or automated tests for localized strings, as mentioned in the integration and why sections.