# Something that can be rendered in dot format.
abstract class DotElement

	# Element ID
	var id: String

	# Element attributes
	var attrs = new AttributeMap

	# Get attribute value for `key`
	fun [](key: String): Object do return attrs[key]

	# Set attribute `value` for `key`
	fun []=(key: String, value: Object) do attrs[key] = value

	# Render `self` to dot format
	fun to_dot: Text do
		var res = new Buffer
		res.append "\"{escape_id}\" "
		if attrs.not_empty then res.append "[{attrs.to_dot(",")}]"
		return res.write_to_string
	end

	# Return `id.escape_to_dot`
	fun escape_id: String do return id.escape_to_dot
end