Class: SPARQL::Algebra::Operator::UUID

Inherits:
Operator::Nullary
  • Object
show all
Includes:
Evaluatable
Defined in:
lib/sparql/algebra/operator/uuid.rb

Overview

The SPARQL uuid function.

[121] BuiltInCall ::= ... | 'UUID' NIL

Examples:

SPARQL Grammar

PREFIX : <http://example.org/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
ASK {
  BIND(UUID() AS ?u1)
  BIND(UUID() AS ?u2)
  FILTER(?u1 != ?u2)
}

SSE

(prefix
 ((: <http://example.org/>) (xsd: <http://www.w3.org/2001/XMLSchema#>))
 (ask
  (filter (!= ?u1 ?u2)
   (extend ((?u1 (uuid)) (?u2 (uuid)))
    (bgp)))))

See Also:

Constant Summary collapse

NAME = 
:uuid

Instance Method Summary collapse

Methods included from Evaluatable

#evaluate, #memoize, #replace_aggregate!, #replace_vars!

Instance Method Details

#apply(**options) ⇒ RDF::URI

Return a fresh IRI from the UUID URN scheme. Each call of UUID() returns a different UUID. It must not be the "nil" UUID (all zeroes). The variant and version of the UUID is implementation dependent.

Returns:

  • (RDF::URI) 


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# File 'lib/sparql/algebra/operator/uuid.rb', line 37

def apply(**options)
  RDF::URI("urn:uuid:#{SecureRandom.uuid}")
end

#to_sparql(**options) ⇒ String

Returns a partial SPARQL grammar for this operator.

Returns:

  • (String) 


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# File 'lib/sparql/algebra/operator/uuid.rb', line 46

def to_sparql(**options)
  "UUID(" + operands.to_sparql(delimiter: ', ', **options) + ")"
end