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Appendix 10 ESP: Element Specification Formats (Normative)

This Standard defines and registers the element specification format eSpec-1, and assigns it the following object identifier:

eSpec-1 {Z39-50-elementSpec 1}

[For a complete list of registered Element Specification Formats, see http://www.loc.gov/z3950/agency/defns/oids.html#11]

ElementSpecificationFormat-eSpec-1 -- For detailed semantics, see Appendix RET.
{Z39-50-elementSpec eSpec-1 (1)} DEFINITIONS ::=

BEGIN

IMPORTS Variant FROM RecordSyntax-generic

StringOrNumeric, InternationalString FROM Z39-50-APDU-1995;

--

Espec-1 ::= SEQUENCE{

	elementSetNames		[1] IMPLICIT SEQUENCE OF InternationalString OPTIONAL,

									-- Origin may include one or more element set names, each

									-- specifying a set of elements. Each of the elements is to be

									-- treated as an elementRequest in the form of simpleElement,

									-- where occurrence is 1. 

	defaultVariantSetId		[2] IMPLICIT OBJECT IDENTIFIER OPTIONAL,

									-- If supplied, applies whenever variantRequest 

									-- does not include variantSetId. 

	defaultVariantRequest	[3] IMPLICIT Variant OPTIONAL,

									-- If supplied, then for each simple elementRequest that does not

 									-- include a variantRequest, the defaultVariantRequest applies.

									-- (defaultVariantRequest does not apply to a compositeRequest.)

	defaultTagType			[4] IMPLICIT INTEGER OPTIONAL,

									-- If supplied, applies whenever 'tagType' (within 'tag' within TagPath) 

									-- is omitted.

	elements				[5] IMPLICIT SEQUENCE OF ElementRequest OPTIONAL}

--

ElementRequest::= CHOICE{

	simpleElement		[1]	 IMPLICIT SimpleElement,

	compositeElement	[2] IMPLICIT SEQUENCE{

						elementList		[1] CHOICE{

									primitives		[1]	 IMPLICIT SEQUENCE OF InternationalString,

															-- Origin may specify one or more element

															-- set names, each identifying a set of elements,

															-- and the composite element is the union.

									specs			[2] IMPLICIT SEQUENCE OF SimpleElement},

						deliveryTag		[2] IMPLICIT TagPath,

													-- DeliveryTag tagPath for compositeElement may not

													-- include wildThing or wildPath.

						variantRequest	[3] IMPLICIT Variant OPTIONAL}}

SimpleElement ::= SEQUENCE{

			path				[1] IMPLICIT TagPath,

			variantRequest	[2] IMPLICIT Variant OPTIONAL}

	

TagPath ::= SEQUENCE OF CHOICE{  

	specificTag	[1] IMPLICIT SEQUENCE{

						tagType	[1] IMPLICIT INTEGER OPTIONAL,

											-- If omitted, then 'defaultTagType' (above) applies, if supplied, and

											-- if not supplied, then default listed in schema applies.

						tagValue	[2] StringOrNumeric,

	 					occurrence	[3] Occurrences OPTIONAL 

											-- default is "first occurrence"

									},

	wildThing	[2] Occurrences,

				  		-- Get Nth "thing" at this level, regardless of tag, for each N specified by

						-- "Occurrences" (which may be 'all' meaning match every element at this level).

						-- E.g., if "Occurrences" is 3, get third element regardless of its tag or the tag of

						-- the first two elements.

	wildPath	[3] IMPLICIT NULL

				  		-- Match any tag, at this level or below, that is on a path for which next tag in this 

				  		-- TagPath sequence occurs. WildPath may not be last member of the TagPath

						-- sequence.

											}

--

Occurrences ::= CHOICE{

	all		[1] IMPLICIT NULL,

	last		[2] IMPLICIT NULL,

	values	[3] IMPLICIT SEQUENCE{

					start		[1] IMPLICIT INTEGER,

									-- if 'start' alone is included, then single occurrence is requested

					howMany	[2] IMPLICIT INTEGER OPTIONAL

									-- For example, if 'start' is 5 and 'howMany' is 6, then request is for

									-- "occurrences 5 through 10."

									}}

END