title: fetch source values from jenkins extended choice parameter
body: <p><a href="https://i.stack.imgur.com/kRc40.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/kRc40.png" alt="Extended Choice Param"></a></p>
  
  <p>I have added an extended choice paramter. Now the source values are lin1, lin2, lin3 as listed in screenshot</p>
  
  <p>now when I run, 
  If I select lin1 then I get param3 = lin1,</p>
  
  <p>If I select lin1 and lin2 then I get param2 - lin1,lin2    ( delimiter is comma )</p>
  
  <p>The question here is, inside jenkins pipeline how can get what all source values were set when the param was created. In short, without selecting any of the checkboxes, want to get the list of the possible values probably in a list</p>
  
  <p>Eg: 
  list1 = some_method(param3)
  // expected output >>  list1 = [lin,lin2,lin3]</p>
  
  <p>Let me know if this description is not clear.</p>
  
  <p>The user who runs this does not have configure access ( we dont want to give configure access to anonynmous user ) Hence the job/config.xml idea will not work here</p>