getypeerd

Getypeerd is a term used in discussions of type systems to describe a class of techniques for retrieving and applying type information at runtime within statically typed languages. In its general form, getypeerd aims to reify type descriptors and carry them alongside values, enabling programs to reason about their own structure without sacrificing compile-time guarantees.

Etymology: The word appears as a portmanteau combining get, type, and erd, with no canonical definition of its origin. It is primarily used in academic papers, blogs, and speculative discussions about runtime type information.

Mechanism: A typical getypeerd approach provides a lightweight representation of a type (a type descriptor), a retrieval API to obtain these descriptors from values or modules, and a reification or code-generation layer that uses descriptors to guide serialization, dispatch, or specialization.

Applications: It can support generic libraries that need to serialize and deserialize data without hard-coding type names, or enable dynamic algorithms that adapt to the concrete types seen at runtime. An example is a serializer that uses a type descriptor to produce compact, self-describing output.

Limitations and challenges: Implementations must balance type safety, performance, and portability. The presence of runtime type information can complicate module boundaries and affect optimizations, and cross-language interoperability remains difficult.

See also: Runtime type information; Reflection; Type erasure; Reification; Generic programming.