Typestring

Typestring is a term used in programming to denote a string representation of a type’s name or identity. It is typically associated with compile-time reflection or metaprogramming, where a typestring is a compile-time constant linked to a specific type. This allows type-aware operations, dispatch, or code generation without requiring a runtime object to represent the type.

In languages that support compile-time reflection, a typestring enables programs to treat type information as data. For example, a function might accept a typestring to select behavior based on the type it represents, or a serialization framework might embed a type name in data to aid deserialization.

Common uses and patterns

- Serialization and deserialization: storing or transmitting the type alongside data to enable correct reconstruction.

- Debugging and logging: including type names in messages to improve diagnostics.

- Metaprogramming and code generation: generating code paths or dispatch tables that depend on type identity.

- Type-safe registries: mapping types to handlers or factories using their typestring as a key.

Relationship to reflection and type-level programming

Typestrings are often a lightweight alternative to full runtime reflection, offering compile-time guarantees about the association between a type and its string representation. They enable type-level reasoning and dispatch while avoiding some runtime overhead or complexity.

Limitations

Not all languages expose type names as stable, runtime-accessible strings. Names may be altered by minification, optimizations, or refactoring, so care is needed to maintain consistency. Across languages, the precise semantics and guarantees of a typestring can vary.

See also: type reflection, type names, type-level programming, serialization.