template <class T>
 struct is_class_or_union
 {
 // SFINAE eliminates this when the type of arg is invalid
 template <class U>
 static yes tester(int U::*arg);
 // overload resolution prefers anything at all over "..."
 template <class U>
 static no tester(...);
 // see which overload is chosen when U == T
 static bool const value
 = sizeof(tester<T>(0)) == sizeof(yes);
 typedef mpl::bool_<value> type;
 };
 struct X{};
 BOOST_STATIC_ASSERT(is_class_or_union<X>::value);
 BOOST_STATIC_ASSERT(!is_class_or_union<int>::value);

C:\PROGRA~1\MICROS~4\VC98\INCLUDE\xutility(19) : error C2679:
 binary '=''std::string' (or there is no acceptable conversion)
 foo.cpp(9) : see reference to function template instantiation
 'class std::back_insert_iterator<class std::map<std::string,
 std::string,struct std::less<std::string>,class
 std::allocator<std::string> > > __cdecl std::copy(class
 std::list<std::string,class std::allocator<std::string>
 >::iterator,class std::list<std::string,class std::allocator<
 std::string> >::iterator,class std::back_insert_iterator<
 class std::map<std::string,std::string,struct std::
 less<std::string>,class std::allocator<std::string> > >)'
 being compiled

self.addEventListener('fetch', function (event) {
  const parsedUrl = url.parse(event.request.url)
  var req = {
    url: parsedUrl.href,
    method: event.request.method,
    body: body,
    headers: {
      'content-type': event.request.headers.get('content-type')
    },
    unpipe: function () {}
  }
  var res = { /* our mock Node http Server Response object */ }
  event.respondWith(new Promise(function (resolve) {
    app(req, res)
  }))
})

// really-need index.js
var _compileStr = Module.prototype._compile.toString();
// pass all arguments from loaded module to our self.require
_compileStr = _compileStr.replace('self.require(path);',
  'self.require.apply(self, arguments);'); // 1
/* jshint -W061 */
var patchedCompile = eval('(' + _compileStr + ')'); // 2
Module.prototype._compile = function(content, filename) {
  return patchedCompile.call(this, content, filename);
};

// @flow

/*::
type MyAlias = {
  foo: number,
  bar: boolean,
  baz: string,
};
*/

function method(value /*: MyAlias */) /*: boolean */ {
  return value.bar;
}

method({ foo: 1, bar: true, baz: ["oops"] });

const add = (a, b) => a + b
add(2, 'foo')

$ npx tsc --noEmit --allowJs app.js 
app.js:9:8 - error TS2345: Argument of type '"foo"' is not assignable 
                           to parameter of type 'number'.

9 add(2, 'foo')
         ~~~~~


Found 1 error.

$ npm install -D cypress

it('adds 2 todos', () => {
  cy.visit('http://localhost:3000')
  cy.get('.new-todo')
    .type('learn testing{enter}')
    .type('be cool{enter}')
  cy.get('.todo-list li')
    .should('have.length', 2)
})

types/
  index.d.ts

package.json
  "types": "types"

{
  "json.schemas": [
    {
      "fileMatch": ["cypress.json"],
      "url": "https://on.cypress.io/cypress.schema.json"
    }
  ]
}

{
  "viewportWidth": 600,
  "viewportHeight": 800,
  "ignoreTestFiles": "answer.js",
  "baseUrl": "http://localhost:3000",
  "$schema": "https://on.cypress.io/cypress.schema.json"
}