Function assertArg

test/angular/1.4/angular.js:1830–1835

* throw error if the argument is falsy.

(arg, name, reason)

 * throw error if the argument is falsy.
 */
function assertArg(arg, name, reason) {
  if (!arg) {
    throw ngMinErr('areq', "Argument '{0}' is {1}", (name || '?'), (reason || "required"));
  }
  return arg;
}

function assertArgFn(arg, name, acceptArrayAnnotation) {
  if (acceptArrayAnnotation && isArray(arg)) {