class Haml::ForceEscapable

Unlike Haml::Escapable, this escapes value even if it’s html_safe.

def initialize(opts = {}) 

def initialize(opts = {})
  super
  @escape_code = options[:escape_code] || "::Haml::Util.escape_html((%s))"
  @escaper = eval("proc {|v| #{@escape_code % 'v'} }")
end

def on_escape(flag, exp)

This method is not used if it's inserted after Haml::Escapable.
ForceEscapable doesn't touch :escape expression. 
def on_escape(flag, exp)
  [:escape, flag, compile(exp)]
end