javascript - How writing text onto specific place [Opal] -

i need write static web page simple data. in form have data user , in tag <div id="prog"> output how using opal writing string specyfic place?

<div id="prog"> </div><script type="text/javascript"> <div id="prog"> </div> </script> pp = document.getelementbyid("prog").innerhtml = opal.main() </script> 

ok, based on sample code, need make opal.main() return string

def main   # logic   return str end 

but think want use opal-jquery or opal-browser, don't have experience later, here's simple example of opal-jquery (of understood asking)

document.ready?    element["form"].on(:submit)     element["#prog].text = element["#input-id"].value   end end