class Prism::DotVisitor

def visit_block_parameters_node(node)

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