JavaScript Objects and Prototype configurable

<html>
  <body></body>
  <script src="display.js"></script>
  <script src="script.js"></script>
</html>

'use strict';

var cat = {
  name: {first: 'Fluffy', last: 'LaBeouf'},
  color: 'White'
};

//Object.defineProperty(cat, 'name', {configurable: false});
//Object.defineProperty(cat, 'name', {writable: true});

delete cat.name

display(cat.name);

function display() {
  for (var i = 0; i < arguments.length; i++) {
    if (typeof arguments[i] === 'object') 
      displayObject(arguments[i])
    else
      displayValue(arguments[i], true)
  }
}

function displayObject(object) {
  if (object == null)
    displayValue('null')
  displayValue(getTypeName(object) + ' {')
  for(var propertyName in object) {
    if (propertyName != 'constructor') {
      displayValue(propertyName + ': ' + object[propertyName], false, true);
    }
  }
  displayValue('}', true)
}

function displayValue(value, addMargin, addPadding) {
  var div = document.createElement('div');
  div.style.fontSize='32px'
  if (addMargin)
    div.style.marginBottom='30px'
  if (addPadding)
    div.style.paddingLeft='30px'
  div.textContent = value;
  document.body.appendChild(div)
}

function getTypeName(object) {
   var funcNameRegex = /function (.{1,})\(/;
   var results = (funcNameRegex).exec(object.constructor.toString());
   return (results && results.length > 1) ? results[1] : "";
}