Method: RDF::Queryable#first

Defined in:
lib/rdf/mixin/queryable.rb

#first ⇒ RDF::Statement #first(pattern) ⇒ RDF::Statement

Queries ‘self` for an RDF statement matching the given `pattern` and returns that statement if found.

Returns ‘nil` if no statements match `pattern`.

Overloads:

Returns:

Since:

  • 0.1.9



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# File 'lib/rdf/mixin/queryable.rb', line 188

def first(pattern = nil)
  if pattern
    query(pattern) do |statement|
      return statement
    end
  elsif respond_to?(:each_statement)
    each_statement do |statement|
      return statement
    end
  else
    return super()
  end
  nil
end