Class: SPARQL::Algebra::Operator::LessThan

Inherits:
Compare show all
Defined in:
lib/sparql/algebra/operator/less_than.rb

Overview

The SPARQL relational < (less than) comparison operator.

[114] RelationalExpression ::= NumericExpression ('<' NumericExpression)?

Examples:

SPARQL Grammar

PREFIX  xsd: <http://www.w3.org/2001/XMLSchema#>
PREFIX  : <http://example.org/things#>
SELECT  ?x
WHERE { ?x :p ?v . FILTER ( ?v < 1 ) }

SSE

(prefix
 ((xsd: <http://www.w3.org/2001/XMLSchema#>) (: <http://example.org/things#>))
 (project (?x) (filter (< ?v 1) (bgp (triple ?x :p ?v)))))

See Also:

Constant Summary collapse

NAME =
:<

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 inherited from Compare

#to_sparql

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_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(left, right, **options) ⇒ RDF::Literal::Boolean

Returns true if the first operand is less than the second operand; returns false otherwise.

Parameters:

  • left (RDF::Literal)

    a literal

  • right (RDF::Literal)

    a literal

Returns:

  • (RDF::Literal::Boolean)

    true or false

Raises:

  • (TypeError)

    if either operand is not a literal



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

def apply(left, right, **options)
  RDF::Literal(super == RDF::Literal(-1))
end