TypMappings

TypMappings, short for Type Mappings, describe how types from one context correspond to types in another. They are typically represented as a mapping from source type identifiers to target type representations, often implemented as a dictionary, registry, or set of transformation rules. TypMappings are used to enable interoperability and data exchange across modules, languages, or layers.

Applications include language interoperability, data serialization, database access, and code generation. They allow a component written in one language to interpret or emit data in another, while preserving type intent such as size, range, and nullability. TypMappings can be resolved statically during compilation or dynamically at runtime.

Design considerations include handling primitive and complex types, parameterized types, and collections; managing nullability; and versioning mappings as schemas evolve. A resolver or prioritization strategy may be needed when multiple sources define mappings. Tooling often validates compatibility between source and target types.

Common implementations use mapping tables, type descriptors, or metadata-driven generators. In serialization, TypMappings map language-native types to wire formats (for example, int to 32-bit integer in JSON or Protobuf). In databases, they map column types to language types for ORM or data access layers.

Limitations and challenges include drift between schemas, maintenance overhead, and performance implications of lookups. Good practices include documentation, explicit versioning, tests for round-trip conversions, and clear fallback strategies.