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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.


              <h3>default UI:</h3>
  <li class="pass">this is for what is true</li>
  <li class="fail">this is for what is false</li>

<ul id="forTest"></ul>


              .pass:before {
  content: "PASS: ";
  color: green;
  font-weight: bold;
.fail:before {
  content: "FAIL: ";
  color: red;
  font-weight: bold;



              // condition为传入判断 true or false 的语句,
// description 为 string
function assert(condition, description) {
  var output = document.getElementById("forTest"); 
  //create li 元素
  var li = document.createElement("li"); 
  // 判断condition为何值,true则li为pass的类,false则为fail的类,
  li.className = condition ? "pass" : "fail"; 
  // 为传入的description定义到变量desp,crteate text node
  var des = document.createTextNode(description)
  //des.className = className; 

var a = 5, b, c = 5;
assert((a === b), "'a == b' is true");
assert((a === c), "'a == c' is false");