title: Pass function argument into getElementById "id"
body: <p>It's a js function that shows various text input forms when you select an apropriate value from a select box.</p>
  
  <pre><code>function arata_formular(formular) {
              document.getElementById("formular").style.visibility = "visible";
              if(document.getElementById("formular").style.display == "none" ) {
                  document.getElementById("formular").style.display = "inline";
              }
              else {
                  document.getElementById("formular").style.display = "visible";
              }
          }
  </code></pre>
  
  <p>But doesn't work as expected. Although it has an argument regardless of what i'll pass into there (lets say arata_formular(entropy) it will still look for the "formular" id not "entropy" one. How can I make the 'inline' insert?</p>
  
  <p>Unfortunately I can't use jquery on this or other frameworks. I must use only javascript. 
  Thanks!</p>