hphp/hack/test/typecheck/immvector.php

   1 <?hh
   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 // Test that the typechecker can correctly handle ImmVector.
  13
  14 // Helpers
  15
  16 function h1(): ImmVector<string> {
  17   return ImmVector {'hello', 'world'};
  18 }
  19
  20 function h2(int $k) : void {}
  21
  22 function h3(string $v) : void {}
  23
  24 // Test that ImmVector {} : ImmVector<int>
  25
  26 function emptyfv(): ImmVector<int> {
  27   return ImmVector {};
  28 }
  29
  30 // Test array-like access.
  31
  32 function simple(ImmVector<int> $fv) : int {
  33   return $fv[0];
  34 }
  35
  36 // Nested FVs.
  37
  38 function nested(): ImmVector<ImmVector<string>> {
  39   return ImmVector {h1(), ImmVector {'a', 'b', 'c'}, ImmVector {}};
  40 }
  41
  42 // Foreach over a FV.
  43
  44 function sum(): int {
  45   $v = ImmVector {1, 2, 3, 4, 5};
  46   $s = 0;
  47   foreach ($v as $k) {
  48     $s += $k;
  49   }
  50   return $s;
  51 }
  52
  53 // Foreach over a FV with both key and value.
  54
  55 function feach(ImmVector<string> $vec) : void {
  56   foreach ($vec as $k => $v) {
  57     h2($k);
  58     h3($v);
  59   }
  60 }
  61
  62 // List syntax
  63
  64 function lsyntax(ImmVector<int> $fv) : void {
  65   list($a, $b) = $fv;
  66 }
  67
  68 // Generic FVs are covariant
  69
  70 class A {
  71 }
  72
  73 class B extends A {
  74 }
  75
  76 function covariance(ImmVector<B> $fvb) : ImmVector<A> {
  77   return $fvb;
  78 }
  79
  80
  81