class SPARQL::Algebra::Operator::NotIn

The SPARQL GraphPattern `in` operator.

Used for filters with more than one expression.

@example

(ask (filter (notin ?o 1 2) (bgp)))

@see www.w3.org/TR/sparql11-query/#func-notin

Constants

NAME

Public Instance Methods

evaluate(bindings, **options) click to toggle source

The NOT IN operator tests whether the RDF term on the left-hand side is not found in the values of list of expressions on the right-hand side. The test is done with “!=” operator, which tests for not the same value, as determined by the operator mapping.

A list of zero terms on the right-hand side is legal.

Errors in comparisons cause the NOT IN expression to raise an error if the RDF term being tested is not found to be in the list elsewhere in the list of terms.

The NOT IN operator is equivalent to the SPARQL expression:

(lhs != expression1) && (lhs != expression2) && ...

NOT IN (…) is equivalent to !(IN (…)).

@example

2 NOT IN (1, 2, 3)  false
2 NOT IN () true
2 NOT IN (<http://example/iri>, "str", 2.0) false
2 NOT IN (1/0, 2)   false
2 NOT IN (2, 1/0)   false
2 NOT IN (3, 1/0)   raises an error

@param [RDF::Query::Solution] bindings

a query solution containing zero or more variable bindings

@param [Hash{Symbol => Object}] options ({})

options passed from query

@return [RDF::Literal::Boolean] `true` or `false` @raise [TypeError] if term is not found and any operand raises an error

# File lib/sparql/algebra/operator/notin.rb, line 45
def evaluate(bindings, **options)
  lhs = operands.first.evaluate(bindings, depth: options[:depth].to_i + 1, **options)
  error_found = false
  found = operands[1..-1].any? do |op|
    begin
      lhs == op.evaluate(bindings, depth: options[:depth].to_i + 1, **options)
    rescue TypeError
      error_found = true
    end
  end
  case
  when found then RDF::Literal::FALSE
  when error_found then raise TypeError
  else RDF::Literal::TRUE
  end
end