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Dictionary Definition Language DDLm

The methods Dictionary Definition Language (DDL) is a proposed formalism for the recording of CIF data names and their definitions and properties within CIF dictionaries, with descriptions of algorithmic methods for evaluation and validation.

While providing important new functionality to dictionary and applications software developers, DDLm fully supports the definition capabilities of the existing dictionary languages, DDL1 and DDL2, but will provide a higher level of semantic content for domain dictionaries. No changes are required in existing archival data files in order to apply domain dictionaries written in DDLm.

Note that the example dictionaries distributed with this draft (cif.dic, cif_core.dic, core_*.dic) are not intended as a proposed implementation of the core dictionary in DDLm, but are just mockups used to trial the DDLm attributes and indicate possible areas of development.

See also the basic DDL1 and relational DDL2 dictionary definition languages.

Current draft

Version 13 August 2008

Previous draft: Version 5 August 2008

Previous draft: Version 13 October 2007

Previous draft: Version 18 March 2007


Updated 6 August 2008

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