User-Defined Literals

User-defined literals (UDLs) let you assign custom semantics to literal values — 100_m means 100 meters, 1.5_rad means radians, and "hello"_sv means string_view. Combined with constexpr and strong types, UDLs enable compile-time unit checking and type conversion, making them a powerful tool for implementing type-safe physical unit libraries.

Chapter Contents

• User-Defined Literal Basics
• UDL in Practice: Type-Safe Unit Systems