hphp/hack/test/typecheck/this_tparam_bad2.php

   1 <?hh // strict
   2 /**
   3  * Copyright (c) 2014, Facebook, Inc.
   4  * All rights reserved.
   5  *
   6  * This source code is licensed under the MIT license found in the
   7  * LICENSE file in the "hack" directory of this source tree.
   8  *
   9  *
  10  */
  11
  12 interface SomethingElse<T> {}
  13
  14 class Foo implements SomethingElse<this> {}
  15
  16 function expects1<T as Foo>(SomethingElse<T> $foo): void {}
  17
  18 function expects2(SomethingElse<Foo> $foo): void {}
  19
  20 function test(Foo $foo): void {
  21   // No error since Foo is an 'as' constraint on a generic
  22   expects1($foo);
  23
  24   // Error because SomethingElse<expression_dependent<Foo>> is different than
  25   // SomethingElse<Foo>
  26   expects2($foo);
  27 }