gistfile1.txt

var _generateGroupId = function randGen(){
  
  // 2. newid is reset  
  var newId = Math.floor(Math.random() * 10);    
  if( _(myArray).include(newId) ){
    // 1. you're sent back to the top of the function
    randGen.apply( this );
  } else {    
    myArray.push( newId );
    // 3. a new id is explicitly returned. if you log here, you will get the new value
    return newId;
  }
    
}