an class='id identifier rubyid_respond_to?'>respond_to?</span><span class='lparen'>(</span><span class='symbol'>:model_name</span><span class='rparen'>)</span> <span class='op'>?</span> <span class='id identifier rubyid_model_or_family_name_or_cst'>model_or_family_name_or_cst</span> <span class='op'>:</span> <span class='kw'>nil</span>
  <span class='kw'>if</span> <span class='id identifier rubyid_comp_name_or_cst_or_class'>comp_name_or_cst_or_class</span><span class='period'>.</span><span class='id identif