Method: RDF::Graph#initialize

Defined in:
lib/rdf/model/graph.rb

#initialize(graph_name: nil, data: nil, **options) {|graph| ... } ⇒ Graph

Note:

Graph names are only useful when used as a projection on a :data which supports named graphs. Otherwise, there is no such thing as a named graph in RDF 1.1, a repository may have graphs which are named, but the name is not a property of the graph.

Returns a new instance of Graph.

Parameters:

  • graph_name (RDF::Resource) (defaults to: nil) —

    The graph_name from the associated Queryable associated with this graph as provided with the :data option (only for Queryable instances supporting named graphs).

  • data (RDF::Queryable) (defaults to: nil) —

    (RDF::Repository.new) Storage behind this graph.

Yields:

  • (graph)

Yield Parameters:

Raises:

  • (ArgumentError) —

    if a data does not support named graphs.



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# File 'lib/rdf/model/graph.rb', line 106

def initialize(graph_name: nil, data: nil, **options, &block)
  @graph_name = case graph_name
    when nil then nil
    when RDF::Resource then graph_name
    else RDF::URI.new(graph_name)
  end

  @options = options.dup
  @data = data || RDF::Repository.new(with_graph_name: false)

  raise ArgumentError, "Can't apply graph_name unless initialized with `data` supporting graph_names" if
    @graph_name && !@data.supports?(:graph_name)

  if block_given?
    case block.arity
      when 1 then block.call(self)
      else instance_eval(&block)
    end
  end
end