Contents

module RDF
  ##
  # @since 0.2.0
  module Countable
    extend RDF::Util::Aliasing::LateBound

    ##
    # Returns `true` if `self` contains no RDF statements.
    #
    # @return [Boolean]
    def empty?
      empty = true
      each { empty = false; break }
      empty
    end

    ##
    # Returns the number of RDF statements in `self`.
    #
    # @return [Integer]
    def count
      count = 0
      each { count += 1 }
      count
    end

    alias_method :size,   :count
    alias_method :length, :count # @deprecated

    ##
    # @private
    # @param  [Symbol, #to_sym] method
    # @return [Enumerator]
    # @see    Object#enum_for
    def enum_for(method = :each, *args)
      # Ensure that enumerators support the `#empty?` and `#count` methods:
      super.extend(RDF::Countable)
    end

    alias_method :to_enum, :enum_for
  end
end

Version data entries

5 entries across 5 versions & 1 rubygems

Version	Path
rdf-0.2.3	lib/rdf/mixin/countable.rb
rdf-0.2.2	lib/rdf/mixin/countable.rb
rdf-0.2.1	lib/rdf/mixin/countable.rb
rdf-0.2.0.1	lib/rdf/mixin/countable.rb
rdf-0.2.0	lib/rdf/mixin/countable.rb