function call as: string_recursive(array, "", statesInString), statesInString and the empty string are constant in this case. The expected output should alert a pop-up with 'Z'.

gistfile1.txt

   var powerSets = new Array();
    powerSets.push("Z");
   
    var statesInString = states.join('');
    statesInString = statesInString.substring(0, numLines); //take the NFA string only
    string_recursive(powerSets,"",statesInString);
    alert(powerSets[0]);
    // for(i = 0; i<powerSetNumber ; i++){
    //     alert(powerSets[i]);
    // }

  }

  function string_recursive($powerSetNumber, $output, $leftOvers){
      
      if($leftOvers.length == 0 && $output!="")
      {
          
          $powerSetNumber.push($output);
          console.log(powerSets);
         
      }

      else
      {
          string_recursive($powerSetNumber ,$output + $leftOvers.charAt(0), $leftOvers.substring(1, $leftOvers.length));
          string_recursive($powerSetNumber ,$output, $leftOvers.substring(1, $leftOvers.length));

      }
      
  }

    var powerSets = new Array();
    powerSets.push("Z");

    var statesInString = states.join('');
    statesInString = statesInString.substring(0, numLines); //take the NFA string only
    string_recursive(powerSets,"",statesInString);
    alert(powerSets[0]);
    // for(i = 0; i<powerSetNumber ; i++){
    //     alert(powerSets[i]);
    // }

  function string_recursive($powerSetNumber, $output, $leftOvers){
      if($leftOvers.length == 0 && $output!="") {
          $powerSetNumber.push($output);
          console.log(powerSets);   
      }
      else
      {
          string_recursive($powerSetNumber ,$output + $leftOvers.charAt(0), $leftOvers.substring(1, $leftOvers.length));
          string_recursive($powerSetNumber ,$output, $leftOvers.substring(1, $leftOvers.length));
      }    
  }

Fuck you and your whitespaces bro 😡

var states = [];
for (i = 0; i < powerSetNumber; i++){
states[i] = String.fromCharCode(myChar.charCodeAt(0) + i);
}

For function call: example: string_recursive(powerSets, "", statesInString);
2nd sample: string_recursive(powerSets,"","abc");
3rd sample: string_recursive(powerSets,"", "abcd")