Crystallographic Information Framework

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DDL dictionary version 2.1.3




    When a data value can be defined as a pre-determined sequence of
    characters, optional characters  or data names (for which the
    definition is also available), it is specified as a construction.
    The rules of construction conform to the the regular expression
    (REGEX) specifications detailed in IEEE (1991).
    Resolved data names for which _item_type_list.construct
    specifications exist are replaced by these constructions,
    otherwise the data-name string is not replaced.

    Ref: IEEE (1991). IEEE Standard for Information Technology -
    Portable Operating System Interface (POSIX) - Part 2: Shell
    and Utilities, Vol. 1, IEEE Standard 1003.2-1992. New York:
    The Institute of Electrical Engineers.


{_year}-{_month}-{_day} typical construction for _date

Type: text

Mandatory item: no

Category: item_type_list