PrefixtoURI

PrefixtoURI is a concept and utility used in data representation to convert prefixed identifiers into full Uniform Resource Identifiers (URIs). It relies on a prefix map that associates short prefixes with longer URI bases, enabling compact notation such as foaf:Person to be expanded to a complete URI like http://xmlns.com/foaf/0.1/Person. This mechanism is common in Semantic Web technologies, knowledge graphs, and linked data workflows.

The basic operation of prefixtoURI takes two inputs: a prefixed term and a prefix map. If the term contains a prefix that is present in the map, the corresponding base URI is concatenated with the local part to form the full URI. If the term is already a full URI, it may be returned unchanged. Prefix declarations may be defined within RDF serializations, SPARQL queries, or external prefix files. Some implementations also support a default base URI to resolve terms without an explicit prefix.

Common usages include simplifying SPARQL queries, RDF serializations, and data publishing where concise identifiers improve readability and maintainability. It is also employed by wiki-like prefix management systems and tooling that converts compact identifiers into dereferenceable links in knowledge graphs. Handling of unknown prefixes, invalid syntax, or conflicting base URIs are typical considerations, with implementations offering error reporting or fallback behaviors.

Example: with the map {foaf: "http://xmlns.com/foaf/0.1/"} a term foaf:Person resolves to http://xmlns.com/foaf/0.1/Person. A term that is already a complete URI would pass through unchanged. PrefixtoURI thus supports efficient, human-friendly URI construction across data formats and systems.