信息技术.主题地图.约束语言(TMCL

[中文适用范围]： 本国际标准定义了一个用于表示主题地图实例数据约束的主题地图词汇，以及用于编写 TMCL 模式的 CTM 模板。它不定义表示主题地图实例数据约束的语法。 [外文原描述]： ISO/IEC 19756:2011 (TMCL) is a constraint language for Topic Maps, allowing definitions of Topic Maps schemas to be written in a precise and machine-readable form. This makes it possible to validate a topic map against a TMCL schema to see if it conforms to the constraints in the schema, and also enables other uses, such as schema-driven editors and object mappings. TMCL is defined as a Topic Maps vocabulary consisting of a number of topic, association, occurrence, and role types, identified by Published Subject Identifiers (PSIs), and defined using English prose. It defines the concept of validation, by which a given topic map is valid according to a schema if it conforms to all the constraints in that schema and a number of global validation rules which apply to all topic maps independent of schema. TMCL does not have any syntax of its own, since it is defined simply as a Topic Maps vocabulary. However, a number of CTM templates are defined in ISO/IEC 19756:2011 in order to facilitate authoring of TMCL schemas using CTM.