Error-Alert

// https://repl.it/@robertaxelkirby/Error-alert-drill

function main() {
  try {
    doAllTheThings();
  }
  catch(e) {
    reportError(e);
  }
}

function doAllTheThings() {
  throw {
    message: "Everything's ruined",
    name: "FatalException",
    toString: function() {
      return `${this.name}: ${this.message}`;
    }
  }
}

function reportError(e) {
  $('.js-error-report').text(`Uh oh, something went wrong! Here's what we know: ${e.message}`);
}

$(main);

Traffic-Lights

// https://repl.it/@robertaxelkirby/Traffic-lights-drill


function doTrafficLights() {
  const activeLight = getActiveLight();
  // your code will replace this call
  // to `console.log()`
  activeLight == 'red' ? 
  turnRed() : 
  activeLight == 'yellow' ? 
  turnYellow() :
  turnGreen();
}

// this function randomly returns red, yellow, or green
// and is called by doTrafficLights.
// don't modify it!
function getActiveLight() {
  return (['red', 'green', 'yellow'])[Math.floor(Math.random() * 3)];
}

/* From here down, you are not expected to 
   understand.... for now :)  
   
   
   Nothing to see here!
   
*/

function turnOffLights() {
  $('.traffic-light').removeClass('yellow-on red-on green-on');
}

function turnGreen() {
  turnOffLights();
  $('.green-light').addClass('green-on');
}

function turnYellow() {
  turnOffLights();
  $('.yellow-light').addClass('yellow-on');
}

function turnRed() {
  turnOffLights();
  $('.red-light').addClass('red-on');
}


function handleClicks() {
  $('.js-control-lights').click(function() {
    doTrafficLights();
  });
}

$(function() {
  turnOffLights();
  handleClicks();
});