ladas-larry

function parseQuery(locationSearch) {
  locationSearch = locationSearch.substring(1); // remove "?" at the beginning
  var values = locationSearch.split('&');
  var queryObj = values.reduce(function (result, item) {
    var parts = item.split('=');
    result[decodeURIComponent(parts[0])] = parts[1];
    return result;
  }, {});
  return queryObj;
}

ladas-larry

//array of objects to array of values
var arr = [{val: 'foo'}, {val: 'bar'}];
arr = arr.map((item) => {
    return item.val;
}); 
console.log(arr) // ['foo', 'bar']


// reversing string
var str = 'abcde'

ladas-larry

function walkTree(node) {
  if (node == null){ 
    return;
   }
  // do something with the current node here
  var childNodes = node.childNodes;
  for (var i = 0; i < childNodes.length; i++) {
    walkTree(node.childNodes[i]);
  }
}

ladas-larry

// Async/await parallelism

async function foo() {
        const [result1, result2] = await Promise.all([
            asyncFunc1(),
            asyncFunc2(),
        ]);
}

ladas-larry

typeof null  //object
NaN === NaN //false
typeof NaN //number

ladas-larry

// if condition
{someName && <div>{someName}</div>} 

//if-else consdition
{ loggedIn && <LogoutButton /> || <LoginButton /> }

ladas-larry

Centering in the Unknown
/* Vertically centering an element of known dimensions inside an element of unknown dimensions */ 
/* image width and height is 24px. Plus 10px padding it comes to 34px. 17px is half of this width and height */ 

.centeredIcon {
  padding: 5px;
  
  position: absolute;
  top: calc(50% - 17px); 

ladas-larry

//Encapsulate conditionals

function shouldShowSpinner(fsm, listNode) {
  return fsm.state === 'fetching' && isEmpty(listNode);
}

if (shouldShowSpinner(fsmInstance, listNodeInstance)) {
  // ...
}

ladas-larry

//Dependency injection

// the Module object
var Module = function (someService) {
    this.someService = someService;
};
Module.prototype.do = function () {
    this.someService.doSomething();
};

ladas-larry

//Rest operator type
 
 ...args: number[]