class RubyXL::SharedStringsTable

def add(v, index = nil)
  index ||= strings.size
  strings[index] =
    case v
    when RubyXL::RichText then v
    when String then RubyXL::RichText.new(:t => RubyXL::Text.new(:value => v))
    when RubyXL::Text               then RubyXL::RichText.new(:t => v)
    when RubyXL::RichTextRun        then RubyXL::RichText.new(:r => [ v ])
    when RubyXL::PhoneticRun        then RubyXL::RichText.new(:r_ph => [ v ])
    when RubyXL::PhoneticProperties then RubyXL::RichText.new(:phonetic_pr => v)
    end
  @index_by_content[v.to_s] = index
end