Sha256: cc1b214f34028c133f2cbacaa430a55690b24725933e55fb036a3216897b83c5
Contents?: true
Size: 760 Bytes
Versions: 5
Compression:
Stored size: 760 Bytes
Contents
module Alf
module Algebra
class Restrict
include Operator
include Relational
include Unary
signature do |s|
s.argument :predicate, Predicate, Predicate.tautology
end
def heading
@heading ||= operand.heading
end
def keys
@keys ||= begin
keys = operand.keys
unless (cv = predicate.constant_variables).empty?
keys = keys.map{|k| k - cv }
end
keys
end
end
private
def _type_check(options)
no_unknown!(predicate.free_variables - operand.attr_list)
rescue NotSupportedError => ex
raise ex if options[:strict]
end
end # class Restrict
end # module Algebra
end # module Alf
Version data entries
5 entries across 5 versions & 1 rubygems