decamelize('blue man group'); // $ExpectType string
decamelize('', ''); // $ExpectError

underscore(); // $ExpectError
underscore('blue man group'); // $ExpectType string
underscore('', ''); // $ExpectError

w(); // $ExpectError
w('blue man group'); // $ExpectType string[]
w('', ''); // $ExpectError

classify(); // $ExpectError
classify('blue man group'); // $ExpectType string
classify('', ''); // $ExpectError

capitalize(); // $ExpectError
capitalize('blue man group'); // $ExpectType string
capitalize('', ''); // $ExpectError

loc(); // $ExpectError
loc("_Hello World");  // $ExpectType string
loc("_Hello %@ %@", ["John", "Smith"]);  // $ExpectType string

const handlebarsSafeString: SafeString = htmlSafe('lorem ipsum...');
htmlSafe('lorem ipsum...'); // $ExpectType SafeString
const regularString: string = htmlSafe('lorem ipsum...'); // $ExpectError

function isSafeTest(a: string | SafeString) {
  if (isHTMLSafe(a)) {
      a = a.toString();
  }

const formatAsCapitalizedStringWithSpaces = (string: string) => capitalize(string.toLowerCase().replace(/[_]/g, ' '));