idFor

Idfor is a term used in software development to denote a mechanism for obtaining a stable identifier for an object, resource, or value. It is not a formal standard, but a convention that appears across languages and frameworks as a function name, property, or utility. The exact behavior of idfor depends on the context: it may extract an existing identifier from a data structure, or it may generate a new, stable identifier from visible properties.

In common usage, idfor serves two related purposes. First, as an identifier extractor, it returns a resource’s primary key or unique field when one is present. This is common in data models and persistence layers where a consistent id is needed for lookups, associations, or serialization. Second, as an identifier generator, it computes a value that uniquely represents an object based on its salient attributes. This can be used to create keys for user interfaces, caches, or tests where an object’s identity must be reproducible.

Implementation patterns vary. Some idfor functions simply access an id field (for example, idfor(obj) = obj.id). Others compute a hash or composite key from several properties if an explicit id is absent. Designers must consider stability (the id should not change unexpectedly), privacy (avoiding sensitive data in identifiers), and collisions (ensuring the generated id remains unique within context).

Because idfor is not standardized, naming conventions differ by language and project. It is frequently seen as idFor in camelCase or as id_for in snake_case. See also getId, primaryKey, and uniqueId.