class Prism::DotVisitor

def visit_hash_node(node)

Visit a HashNode node. 
def visit_hash_node(node)
  table = Table.new("HashNode")
  id = node_id(node)
  # opening_loc
  table.field("opening_loc", location_inspect(node.opening_loc))
  # elements
  if node.elements.any?
    table.field("elements", port: true)
    waypoint = "#{id}_elements"
    digraph.waypoint("#{waypoint};")
    digraph.edge("#{id}:elements -> #{waypoint};")
    node.elements.each { |child| digraph.edge("#{waypoint} -> #{node_id(child)};") }
  else
    table.field("elements", "[]")
  end
  # closing_loc
  table.field("closing_loc", location_inspect(node.closing_loc))
  digraph.nodes << <<~DOT
    #{id} [
      label=<#{table.to_dot.gsub(/\n/, "\n  ")}>
    ];
  DOT
  super
end