basistyps

Basistyps are a concept used in programming language theory to denote the primitive data types that form the foundational layer of a language’s type system. They are intended to be irreducible representations of data within that system, providing the basic meaning and operations that other types are built upon. The exact set of basistyps varies by language, but they typically include boolean values, integers, floating-point numbers, characters, and sometimes a unit type or a null/void type. In some languages, strings or arrays are defined in terms of basistyps and other composite types rather than being primitive.

As building blocks, basistyps underpin the construction of more complex types such as tuples, records, lists, maps, and function types. They also influence type safety, memory layout decisions, and the kinds of operations that are well-defined for values of a given type. Some type systems distinguish multiple subcategories within basistyps, such as signed versus unsigned integers or different numeric domains (natural numbers, real numbers, etc.), while others adopt a minimal, uniform set.

There is no universal agreement on the exact composition of basistyps, reflecting trade-offs between expressiveness, simplicity, and implementation complexity. A minimal set supports straightforward inference and robust optimization, whereas a richer set can reduce the need for boilerplate at the cost of greater complexity in the compiler and type checker. Basistyps remain a central reference point for discussions of language design and type theory.

See also: Primitive type, Type system, Type inference, Data model.