Atnotation

Atnotation is a notation convention that uses the at symbol (@) to attach metadata or attributes to elements within a formal language, data model, or text. It is intended to be lightweight and portable, allowing authors to annotate objects without changing their core syntax.

Syntax and forms vary by community. A common pattern places annotations after an entity, for example: object @role(admin), document @timestamp(2025-12-07T12:00Z). Another variant uses a prefix form such as @role: admin or @tag[color=blue]. Some implementations support hierarchical annotations, like section.subsection @id(abc). The essential idea is that '@' introduces a tag and is followed by a value or small payload.

Applications and uses. In programming, it resembles decorators or attributes, enabling tools to attach behavior or metadata at compile time or runtime. In data modeling and serialization, atnotation can carry provenance, access controls, or processing hints without altering primary data structures. In linguistics and textual annotation, it provides a concise way to mark features or roles.

Status and reception. Atnotation is not a widely standardized term. It remains a niche or experimental concept used in domain-specific languages, document grammars, or prototype tools. Different communities may adopt different syntax and semantics.

See also. Related concepts include annotations, metadata, decorator patterns, attribute grammars, and the at sign.