class Roda::RodaPlugins::ErubisEscaping::UnsafeClassEscaper

classes marked as safe.
Escaper which escapes by default, but does not escape instances of

def escape_xml(string)

given object is not already a string, convert it to a string first.
classes, escape it, otherwise return it verbatim. If the
If the string given is not an instance of one of the safe 
def escape_xml(string)
  unless string.is_a?(String)
    string = string.to_s
  end
  if @safe_classes.any?{|c| string.is_a?(c)}
    string
  else
    Escaper.escape_xml(string)
  end
end

def initialize(safe_classes)

Record the classes to consider safe. 
def initialize(safe_classes)
  @safe_classes = Array(safe_classes).freeze
  freeze
end