Class: SPARQL::Algebra::Operator::Subtract

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

Overview

The SPARQL numeric subtract operator. (- ?x ?y) (subtract ?x ?y)

See Also:

Constant Summary

NAME =
[:-, :subtract]

Constants inherited from Binary

Binary::ARITY

Constants inherited from SPARQL::Algebra::Operator

ARITY

Instance Attribute Summary

Attributes inherited from SPARQL::Algebra::Operator

#operands, #options

Instance Method Summary (collapse)

Methods included from Evaluatable

#evaluate, #memoize

Methods inherited from Binary

#initialize

Methods inherited from SPARQL::Algebra::Operator

arity, base_uri, #base_uri, base_uri=, #boolean, #constant?, #eql?, #evaluatable?, evaluate, #executable?, for, #initialize, #inspect, #operand, #optimize, prefixes, #prefixes, prefixes=, #to_sse, #to_sxp, #variable?

Methods included from Expression

cast, #constant?, #evaluate, for, new, open, #optimize, parse, #to_sse, #variable?

Constructor Details

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

Instance Method Details

- (RDF::Literal::Numeric) apply(left, right)

Returns the arithmetic difference of the operands.

Parameters:

  • left (RDF::Literal::Numeric)

    a numeric literal

  • right (RDF::Literal::Numeric)

    a numeric literal

Returns:

  • (RDF::Literal::Numeric)

Raises:

  • (TypeError)

    if either operand is not a numeric literal



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# File 'lib/sparql/algebra/operator/subtract.rb', line 23

def apply(left, right)
  case
    when left.is_a?(RDF::Literal::Numeric) && right.is_a?(RDF::Literal::Numeric)
      left - right
    else raise TypeError, "expected two RDF::Literal::Numeric operands, but got #{left.inspect} and #{right.inspect}"
  end
end