hphp/hack/test/typecheck/expression_trees/splice_state.php

   1 <?hh
   2
   3 <<file:__EnableUnstableFeatures('expression_trees')>>
   4
   5 class Foo {
   6   public ?int $x;
   7   public function reset(): int {
   8     return 1;
   9   }
  10 }
  11
  12 function lift<T>(T $_): ExprTree<Code, Code::TAst, T> {
  13   throw new Exception();
  14 }
  15
  16 // This technically shouldn't throw an error.
  17 // It currently is due to typechecking the current desugaring
  18 // So, for the moment, allow this error to be thrown and fix the desugaring
  19 function test(): void {
  20   $x = new Foo();
  21
  22   if ($x->x !== null) {
  23     $_ = Code`() ==> {
  24       // We know that $x->x is not null
  25       __splice__(lift($x->x + 1));
  26       return;
  27     }`;
  28   }
  29 }
  30
  31 //// BEGIN DEFS
  32 // Placeholder definition so we don't get naming/typing errors.
  33 final class Code {
  34   const type TAst = mixed;
  35   // Simple literals.
  36   public function intLiteral(?ExprPos $_, int $_): this::TAst {
  37     throw new Exception();
  38   }
  39   public function boolLiteral(?ExprPos $_, bool $_): this::TAst {
  40     throw new Exception();
  41   }
  42   public function stringLiteral(?ExprPos $_, string $_): this::TAst {
  43     throw new Exception();
  44   }
  45   public function nullLiteral(?ExprPos $_): this::TAst {
  46     throw new Exception();
  47   }
  48   public function localVar(?ExprPos $_, string $_): this::TAst {
  49     throw new Exception();
  50   }
  51   public function lambdaLiteral(
  52     ?ExprPos $_,
  53     vec<string> $_args,
  54     vec<this::TAst> $_body,
  55   ): this::TAst {
  56     throw new Exception();
  57   }
  58
  59   // Operators
  60   public function plus(
  61     ?ExprPos $_,
  62     this::TAst $_,
  63     this::TAst $_,
  64   ): this::TAst {
  65     throw new Exception();
  66   }
  67   public function ampamp(
  68     ?ExprPos $_,
  69     this::TAst $_,
  70     this::TAst $_,
  71   ): this::TAst {
  72     throw new Exception();
  73   }
  74   public function barbar(
  75     ?ExprPos $_,
  76     this::TAst $_,
  77     this::TAst $_,
  78   ): this::TAst {
  79     throw new Exception();
  80   }
  81   public function exclamationMark(
  82     ?ExprPos $_,
  83     this::TAst $_,
  84   ): this::TAst {
  85     throw new Exception();
  86   }
  87   public function call(
  88     ?ExprPos $_,
  89     string $_fnName,
  90     vec<this::TAst> $_args,
  91   ): this::TAst {
  92     throw new Exception();
  93   }
  94
  95   public function assign(
  96     ?ExprPos $_,
  97     this::TAst $_,
  98     this::TAst $_,
  99   ): this::TAst {
 100     throw new Exception();
 101   }
 102
 103   // Statements.
 104   public function ifStatement(
 105     ?ExprPos $_,
 106     this::TAst $_cond,
 107     vec<this::TAst> $_then_body,
 108     vec<this::TAst> $_else_body,
 109   ): this::TAst {
 110     throw new Exception();
 111   }
 112   public function whileStatement(
 113     ?ExprPos $_,
 114     this::TAst $_cond,
 115     vec<this::TAst> $_body,
 116   ): this::TAst {
 117     throw new Exception();
 118   }
 119   public function returnStatement(
 120     ?ExprPos $_,
 121     ?this::TAst $_,
 122   ): this::TAst {
 123     throw new Exception();
 124   }
 125   public function forStatement(
 126     ?ExprPos $_,
 127     vec<this::TAst> $_,
 128     this::TAst $_,
 129     vec<this::TAst> $_,
 130     vec<this::TAst> $_,
 131   ): this::TAst {
 132     throw new Exception();
 133   }
 134   public function breakStatement(?ExprPos $_): this::TAst {
 135     throw new Exception();
 136   }
 137   public function continueStatement(?ExprPos $_,): this::TAst {
 138     throw new Exception();
 139   }
 140
 141   // Splice
 142   public function splice<T>(
 143     ?ExprPos $_,
 144     ExprTree<this, this::TAst, T> $_,
 145   ): this::TAst {
 146     throw new Exception();
 147   }
 148
 149   // TODO: Discard unsupported syntax nodes while lowering
 150   public function unsupportedSyntax(string $msg): this::TAst {
 151     throw new Exception($msg);
 152   }
 153 }
 154
 155 final class ExprTree<TVisitor, TResult, TInfer>{
 156   public function __construct(
 157     private ?ExprPos $pos,
 158     private (function(TVisitor): TResult) $x,
 159     private (function(): TInfer) $err,
 160   ) {}
 161 }
 162
 163 final class ExprPos {
 164   public function __construct(
 165     private int $begin_line,
 166     private int $begin_col,
 167     private int $end_line,
 168     private int $end_col,
 169   ) {}
 170 }
 171 //// END DEFS