Class: SPARQL::Algebra::Operator::StrDT

Inherits:
Binary show all
Includes:
Evaluatable
Defined in:
lib/sparql/algebra/operator/strdt.rb

Overview

The SPARQL strdt operator.

[121] BuiltInCall ::= … | ‘STRDT’ ‘(’ Expression ‘,’ Expression ‘)’

Examples:

SPARQL Grammar

PREFIX : <http://example.org/>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>
SELECT ?s (STRDT(?str,xsd:string) AS ?str1) WHERE {
  ?s :str ?str
  FILTER(LANGMATCHES(LANG(?str), "en"))
}

SSE

(prefix
 ((: <http://example.org/>) (xsd: <http://www.w3.org/2001/XMLSchema#>))
  (project (?s ?str1)
    (extend ((?str1 (strdt ?str xsd:string)))
      (filter (langMatches (lang ?str) "en")
        (bgp (triple ?s :str ?str))))))

See Also:

Constant Summary collapse

NAME = 
:strdt

Constants inherited from Binary

Binary::ARITY

Constants inherited from SPARQL::Algebra::Operator

ARITY, IsURI, URI

Constants included from Expression

Expression::PATTERN_PARENTS

Instance Attribute Summary

Attributes inherited from SPARQL::Algebra::Operator

#operands

Instance Method Summary collapse

Methods included from Evaluatable

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

Methods inherited from Binary

#initialize

Methods inherited from SPARQL::Algebra::Operator

#aggregate?, arity, #base_uri, base_uri, base_uri=, #bind, #boolean, #constant?, #deep_dup, #each_descendant, #eql?, #evaluatable?, evaluate, #executable?, #first_ancestor, for, #initialize, #inspect, #ndvars, #node?, #operand, #optimize, #optimize!, #parent, #parent=, #prefixes, prefixes, prefixes=, #rewrite, #to_binary, to_sparql, #to_sxp, #to_sxp_bin, #validate!, #variable?, #variables, #vars

Methods included from Expression

cast, #constant?, #evaluate, extension, extension?, extensions, for, #invalid?, new, #node?, open, #optimize, #optimize!, parse, register_extension, #to_sxp_bin, #valid?, #validate!, #variable?

Constructor Details

This class inherits a constructor from SPARQL::Algebra::Operator::Binary

Instance Method Details

#apply(value, datatypeIRI, **options) ⇒ RDF::Literal

Constructs a literal with lexical form and type as specified by the arguments.

Parameters:

  • value (RDF::Literal) —

    a literal

  • datatypeIRI (RDF::URI) —

    datatype

Returns:

  • (RDF::Literal) —

    a datatyped literal

Raises:

  • (TypeError)

See Also:



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# File 'lib/sparql/algebra/operator/strdt.rb', line 39

def apply(value, datatypeIRI, **options)
  raise TypeError, "Literal #{value.inspect} is not simple" unless value.simple?
  RDF::Literal.new(value.to_s, datatype: datatypeIRI)
end

#to_sparql(**options) ⇒ String

Returns a partial SPARQL grammar for this operator.

Returns:

  • (String) 


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# File 'lib/sparql/algebra/operator/strdt.rb', line 49

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