# File lib/asciidoctor/document.rb, line 887
  def apply_attribute_value_subs(value)
    if (m = AttributeEntryPassMacroRx.match(value))
      if !m[1].empty?
        subs = resolve_pass_subs m[1]
        subs.empty? ? m[2] : (apply_subs m[2], subs)
      else
        m[2]
      end
    else
      apply_header_subs value
    end
  end