valuetypeyear

valuetypeyear is a conceptual data type used in programming and data modeling to represent a calendar year without specifying a month or day. It encapsulates year information as a discrete value, enabling year-level validation, storage, and operations separate from full date or timestamp types.

Design and semantics: valuetypeyear typically stores the year as a non-negative integer, with common practical bounds such as 1 to 9999 or a broader range in extended systems. It enforces invariants that prevent invalid years (for example, negative values in systems that do not support BCE). The type supports basic comparison operators (equal, not equal, less than, greater than) and arithmetic such as adding or subtracting a number of years. Conversions to and from string representations (for example "2024") and interoperability with full date types through conversion routines are standard features. It is distinct from a complete date type, which includes month and day information.

Implementation considerations: valuetypeyear is often realized as a lightweight wrapper around an underlying integer or as a dedicated primitive in languages that expose specialized value types. The memory footprint is typically small, commonly four bytes for the integer representation. Construction-time validation ensures only valid year values are produced. When exchanging data with external systems, standardized formats like ISO 8601 year representations or fixed-width strings are commonly used.

Use cases: valuable in historical datasets, fiscal or academic calendars, and temporal indexing where month and day are irrelevant. It facilitates year-level filtering, grouping, and indexing, and can be serialized for storage in databases as integers or fixed-length strings. See also related types such as valuetypemonth and full date types for broader temporal modeling.