Listasi

Listasi is a specification for representing structured lists in digital content and data interchange. It provides a declarative syntax and a set of constraints to describe lists, their items, and associated metadata. The goal is to enable consistent rendering, validation, and localization of lists across applications, APIs, and documents.

Name and origin: The term Listasi combines the Latin-derived word lista with a suffix -si to denote a standard specification. It originated from the Listasi Consortium, formed by content-technology researchers and CMS developers in the early 2010s. The first public draft appeared in 2013, with successive revisions.

Core concepts: The specification defines a ListasiDocument containing one or more ListasiItem elements. Each item may include fields such as title, value, label, metadata, and an optional sublist for nesting. Lists may be ordered or unordered, carry constraints such as uniqueness of item values, and support localization via translatedLabel fields.

Serialization and rendering: Listasi documents are designed to be serialized in JSON, YAML, or XML. A separate rendering profile describes how to present lists in different contexts (web, print, assistive technologies). Accessibility considerations include ARIA roles and proper labeling.

Adoption and impact: Listasi has been adopted by several content platforms and e-commerce catalogs to ensure uniform list semantics. Critics argue that the specification adds complexity for simple lists. Future work focuses on streaming large lists and improving validation performance.

See also: List; Data serialization formats; Schema languages; Accessibility.