mcs/mcs/dynamic.cs

   1 //
   2 // dynamic.cs: support for dynamic expressions
   3 //
   4 // Authors: Marek Safar (marek.safar@gmail.com)
   5 //
   6 // Dual licensed under the terms of the MIT X11 or GNU GPL
   7 //
   8 // Copyright 2009 Novell, Inc
   9 //
  10
  11 using System;
  12 using System.Linq;
  13 using SLE = System.Linq.Expressions;
  14
  15 #if NET_4_0
  16 using System.Dynamic;
  17 #endif
  18
  19 namespace Mono.CSharp
  20 {
  21         //
  22         // A copy of Microsoft.CSharp/Microsoft.CSharp.RuntimeBinder/CSharpBinderFlags.cs
  23         // has to be kept in sync
  24         //
  25         [Flags]
  26         public enum CSharpBinderFlags
  27         {
  28                 None = 0,
  29                 CheckedContext = 1,
  30                 InvokeSimpleName = 1 << 1,
  31                 InvokeSpecialName = 1 << 2,
  32                 BinaryOperationLogical = 1 << 3,
  33                 ConvertExplicit = 1 << 4,
  34                 ConvertArrayIndex = 1 << 5,
  35                 ResultIndexed = 1 << 6,
  36                 ValueFromCompoundAssignment = 1 << 7,
  37                 ResultDiscarded = 1 << 8
  38         }
  39
  40         //
  41         // Type expression with internal dynamic type symbol
  42         //
  43         class DynamicTypeExpr : TypeExpr
  44         {
  45                 public DynamicTypeExpr (Location loc)
  46                 {
  47                         this.loc = loc;
  48                 }
  49
  50                 public override TypeSpec ResolveAsType (IMemberContext ec)
  51                 {
  52                         eclass = ExprClass.Type;
  53                         type = ec.Module.Compiler.BuiltinTypes.Dynamic;
  54                         return type;
  55                 }
  56         }
  57
  58         #region Dynamic runtime binder expressions
  59
  60         //
  61         // Expression created from runtime dynamic object value by dynamic binder
  62         //
  63         public class RuntimeValueExpression : Expression, IDynamicAssign, IMemoryLocation
  64         {
  65 #if !NET_4_0
  66                 public class DynamicMetaObject
  67                 {
  68                         public TypeSpec RuntimeType;
  69                         public TypeSpec LimitType;
  70                         public SLE.Expression Expression;
  71                 }
  72 #endif
  73
  74                 readonly DynamicMetaObject obj;
  75
  76                 public RuntimeValueExpression (DynamicMetaObject obj, TypeSpec type)
  77                 {
  78                         this.obj = obj;
  79                         this.type = type;
  80                         this.eclass = ExprClass.Variable;
  81                 }
  82
  83                 #region Properties
  84
  85                 public bool IsSuggestionOnly { get; set; }
  86
  87                 public DynamicMetaObject MetaObject {
  88                         get { return obj; }
  89                 }
  90
  91                 #endregion
  92
  93                 public void AddressOf (EmitContext ec, AddressOp mode)
  94                 {
  95                         throw new NotImplementedException ();
  96                 }
  97
  98                 public override bool ContainsEmitWithAwait ()
  99                 {
 100                         throw new NotSupportedException ();
 101                 }
 102
 103                 public override Expression CreateExpressionTree (ResolveContext ec)
 104                 {
 105                         throw new NotSupportedException ();
 106                 }
 107
 108                 protected override Expression DoResolve (ResolveContext ec)
 109                 {
 110                         return this;
 111                 }
 112
 113                 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
 114                 {
 115                         return this;
 116                 }
 117
 118                 public override void Emit (EmitContext ec)
 119                 {
 120                         throw new NotImplementedException ();
 121                 }
 122
 123                 #region IAssignMethod Members
 124
 125                 public void Emit (EmitContext ec, bool leave_copy)
 126                 {
 127                         throw new NotImplementedException ();
 128                 }
 129
 130                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
 131                 {
 132                         throw new NotImplementedException ();
 133                 }
 134
 135                 #endregion
 136
 137                 public SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source)
 138                 {
 139                         return obj.Expression;
 140                 }
 141
 142                 public override SLE.Expression MakeExpression (BuilderContext ctx)
 143                 {
 144 #if STATIC
 145                         return base.MakeExpression (ctx);
 146 #else
 147
 148         #if NET_4_0
 149                                 if (type.IsStruct && !obj.Expression.Type.IsValueType)
 150                                         return SLE.Expression.Unbox (obj.Expression, type.GetMetaInfo ());
 151
 152                                 if (obj.Expression.NodeType == SLE.ExpressionType.Parameter) {
 153                                         if (((SLE.ParameterExpression) obj.Expression).IsByRef)
 154                                                 return obj.Expression;
 155                                 }
 156         #endif
 157
 158                                 return SLE.Expression.Convert (obj.Expression, type.GetMetaInfo ());
 159 #endif
 160                 }
 161         }
 162
 163         //
 164         // Wraps runtime dynamic expression into expected type. Needed
 165         // to satify expected type check by dynamic binder and no conversion
 166         // is required (ResultDiscarded).
 167         //
 168         public class DynamicResultCast : ShimExpression
 169         {
 170                 public DynamicResultCast (TypeSpec type, Expression expr)
 171                         : base (expr)
 172                 {
 173                         this.type = type;
 174                 }
 175
 176                 protected override Expression DoResolve (ResolveContext ec)
 177                 {
 178                         expr = expr.Resolve (ec);
 179                         eclass = ExprClass.Value;
 180                         return this;
 181                 }
 182
 183 #if NET_4_0
 184                 public override SLE.Expression MakeExpression (BuilderContext ctx)
 185                 {
 186 #if STATIC
 187                         return base.MakeExpression (ctx);
 188 #else
 189                         return SLE.Expression.Block (expr.MakeExpression (ctx), SLE.Expression.Default (type.GetMetaInfo ()));
 190 #endif
 191                 }
 192 #endif
 193         }
 194
 195         #endregion
 196
 197         //
 198         // Creates dynamic binder expression
 199         //
 200         interface IDynamicBinder
 201         {
 202                 Expression CreateCallSiteBinder (ResolveContext ec, Arguments args);
 203         }
 204
 205         //
 206         // Extends standard assignment interface for expressions
 207         // supported by dynamic resolver
 208         //
 209         interface IDynamicAssign : IAssignMethod
 210         {
 211                 SLE.Expression MakeAssignExpression (BuilderContext ctx, Expression source);
 212         }
 213
 214         //
 215         // Base dynamic expression statement creator
 216         //
 217         class DynamicExpressionStatement : ExpressionStatement
 218         {
 219                 //
 220                 // Binder flag dynamic constant, the value is combination of
 221                 // flags known at resolve stage and flags known only at emit
 222                 // stage
 223                 //
 224                 protected class BinderFlags : EnumConstant
 225                 {
 226                         DynamicExpressionStatement statement;
 227                         CSharpBinderFlags flags;
 228
 229                         public BinderFlags (CSharpBinderFlags flags, DynamicExpressionStatement statement)
 230                                 : base (statement.loc)
 231                         {
 232                                 this.flags = flags;
 233                                 this.statement = statement;
 234                                 eclass = 0;
 235                         }
 236
 237                         protected override Expression DoResolve (ResolveContext ec)
 238                         {
 239                                 Child = new IntConstant (ec.BuiltinTypes, (int) (flags | statement.flags), statement.loc);
 240
 241                                 type = ec.Module.PredefinedTypes.BinderFlags.Resolve ();
 242                                 eclass = Child.eclass;
 243                                 return this;
 244                         }
 245                 }
 246
 247                 readonly Arguments arguments;
 248                 protected IDynamicBinder binder;
 249                 protected Expression binder_expr;
 250
 251                 // Used by BinderFlags
 252                 protected CSharpBinderFlags flags;
 253
 254                 TypeSpec binder_type;
 255                 TypeParameter[] context_mvars;
 256
 257                 public DynamicExpressionStatement (IDynamicBinder binder, Arguments args, Location loc)
 258                 {
 259                         this.binder = binder;
 260                         this.arguments = args;
 261                         this.loc = loc;
 262                 }
 263
 264                 public Arguments Arguments {
 265                         get {
 266                                 return arguments;
 267                         }
 268                 }
 269
 270                 public override Expression CreateExpressionTree (ResolveContext ec)
 271                 {
 272                         ec.Report.Error (1963, loc, "An expression tree cannot contain a dynamic operation");
 273                         return null;
 274                 }
 275
 276                 protected override Expression DoResolve (ResolveContext rc)
 277                 {
 278                         if (DoResolveCore (rc))
 279                                 binder_expr = binder.CreateCallSiteBinder (rc, arguments);
 280
 281                         return this;
 282                 }
 283
 284                 protected bool DoResolveCore (ResolveContext rc)
 285                 {
 286                         if (rc.CurrentTypeParameters != null && rc.CurrentTypeParameters[0].IsMethodTypeParameter)
 287                                 context_mvars = rc.CurrentTypeParameters;
 288
 289                         int errors = rc.Report.Errors;
 290                         var pt = rc.Module.PredefinedTypes;
 291
 292                         binder_type = pt.Binder.Resolve ();
 293                         pt.CallSite.Resolve ();
 294                         pt.CallSiteGeneric.Resolve ();
 295
 296                         eclass = ExprClass.Value;
 297
 298                         if (type == null)
 299                                 type = rc.BuiltinTypes.Dynamic;
 300
 301                         if (rc.Report.Errors == errors)
 302                                 return true;
 303
 304                         rc.Report.Error (1969, loc,
 305                                 "Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference");
 306                         return false;
 307                 }
 308
 309                 public override void Emit (EmitContext ec)
 310                 {
 311                         EmitCall (ec, binder_expr, arguments,  false);
 312                 }
 313
 314                 public override void EmitStatement (EmitContext ec)
 315                 {
 316                         EmitCall (ec, binder_expr, arguments, true);
 317                 }
 318
 319                 protected void EmitCall (EmitContext ec, Expression binder, Arguments arguments, bool isStatement)
 320                 {
 321                         //
 322                         // This method generates all internal infrastructure for a dynamic call. The
 323                         // reason why it's quite complicated is the mixture of dynamic and anonymous
 324                         // methods. Dynamic itself requires a temporary class (ContainerX) and anonymous
 325                         // methods can generate temporary storey as well (AnonStorey). Handling MVAR
 326                         // type parameters rewrite is non-trivial in such case as there are various
 327                         // combinations possible therefore the mutator is not straightforward. Secondly
 328                         // we need to keep both MVAR(possibly VAR for anon storey) and type VAR to emit
 329                         // correct Site field type and its access from EmitContext.
 330                         //
 331
 332                         int dyn_args_count = arguments == null ? 0 : arguments.Count;
 333                         int default_args = isStatement ? 1 : 2;
 334                         var module = ec.Module;
 335
 336                         bool has_ref_out_argument = false;
 337                         var targs = new TypeExpression[dyn_args_count + default_args];
 338                         targs[0] = new TypeExpression (module.PredefinedTypes.CallSite.TypeSpec, loc);
 339
 340                         TypeExpression[] targs_for_instance = null;
 341                         TypeParameterMutator mutator;
 342
 343                         var site_container = ec.CreateDynamicSite ();
 344
 345                         if (context_mvars != null) {
 346                                 TypeParameter[] tparam;
 347                                 TypeContainer sc = site_container;
 348                                 do {
 349                                         tparam = sc.CurrentTypeParameters;
 350                                         sc = sc.Parent;
 351                                 } while (tparam == null);
 352
 353                                 mutator = new TypeParameterMutator (context_mvars, tparam);
 354
 355                                 if (!ec.IsAnonymousStoreyMutateRequired) {
 356                                         targs_for_instance = new TypeExpression[targs.Length];
 357                                         targs_for_instance[0] = targs[0];
 358                                 }
 359                         } else {
 360                                 mutator = null;
 361                         }
 362
 363                         for (int i = 0; i < dyn_args_count; ++i) {
 364                                 Argument a = arguments[i];
 365                                 if (a.ArgType == Argument.AType.Out || a.ArgType == Argument.AType.Ref)
 366                                         has_ref_out_argument = true;
 367
 368                                 var t = a.Type;
 369
 370                                 // Convert any internal type like dynamic or null to object
 371                                 if (t.Kind == MemberKind.InternalCompilerType)
 372                                         t = ec.BuiltinTypes.Object;
 373
 374                                 if (targs_for_instance != null)
 375                                         targs_for_instance[i + 1] = new TypeExpression (t, loc);
 376
 377                                 if (mutator != null)
 378                                         t = t.Mutate (mutator);
 379
 380                                 targs[i + 1] = new TypeExpression (t, loc);
 381                         }
 382
 383                         TypeExpr del_type = null;
 384                         TypeExpr del_type_instance_access = null;
 385                         if (!has_ref_out_argument) {
 386                                 string d_name = isStatement ? "Action" : "Func";
 387
 388                                 TypeExpr te = null;
 389                                 Namespace type_ns = module.GlobalRootNamespace.GetNamespace ("System", true);
 390                                 if (type_ns != null) {
 391                                         te = type_ns.LookupType (module, d_name, dyn_args_count + default_args, LookupMode.Normal, loc);
 392                                 }
 393
 394                                 if (te != null) {
 395                                         if (!isStatement) {
 396                                                 var t = type;
 397                                                 if (t.Kind == MemberKind.InternalCompilerType)
 398                                                         t = ec.BuiltinTypes.Object;
 399
 400                                                 if (targs_for_instance != null)
 401                                                         targs_for_instance[targs_for_instance.Length - 1] = new TypeExpression (t, loc);
 402
 403                                                 if (mutator != null)
 404                                                         t = t.Mutate (mutator);
 405
 406                                                 targs[targs.Length - 1] = new TypeExpression (t, loc);
 407                                         }
 408
 409                                         del_type = new GenericTypeExpr (te.Type, new TypeArguments (targs), loc);
 410                                         if (targs_for_instance != null)
 411                                                 del_type_instance_access = new GenericTypeExpr (te.Type, new TypeArguments (targs_for_instance), loc);
 412                                         else
 413                                                 del_type_instance_access = del_type;
 414                                 }
 415                         }
 416
 417                         //
 418                         // Create custom delegate when no appropriate predefined delegate has been found
 419                         //
 420                         Delegate d;
 421                         if (del_type == null) {
 422                                 TypeSpec rt = isStatement ? ec.BuiltinTypes.Void : type;
 423                                 Parameter[] p = new Parameter[dyn_args_count + 1];
 424                                 p[0] = new Parameter (targs[0], "p0", Parameter.Modifier.NONE, null, loc);
 425
 426                                 var site = ec.CreateDynamicSite ();
 427                                 int index = site.Types == null ? 0 : site.Types.Count;
 428
 429                                 if (mutator != null)
 430                                         rt = mutator.Mutate (rt);
 431
 432                                 for (int i = 1; i < dyn_args_count + 1; ++i) {
 433                                         p[i] = new Parameter (targs[i], "p" + i.ToString ("X"), arguments[i - 1].Modifier, null, loc);
 434                                 }
 435
 436                                 d = new Delegate (site.NamespaceEntry, site, new TypeExpression (rt, loc),
 437                                         Modifiers.INTERNAL | Modifiers.COMPILER_GENERATED,
 438                                         new MemberName ("Container" + index.ToString ("X")),
 439                                         new ParametersCompiled (p), null);
 440
 441                                 d.CreateType ();
 442                                 d.DefineType ();
 443                                 d.Define ();
 444                                 d.Emit ();
 445
 446                                 site.AddDelegate (d);
 447                                 del_type = new TypeExpression (d.CurrentType, loc);
 448                                 if (targs_for_instance != null) {
 449                                         del_type_instance_access = null;
 450                                 } else {
 451                                         del_type_instance_access = del_type;
 452                                 }
 453                         } else {
 454                                 d = null;
 455                         }
 456
 457                         var site_type_decl = new GenericTypeExpr (module.PredefinedTypes.CallSiteGeneric.TypeSpec, new TypeArguments (del_type), loc);
 458                         var field = site_container.CreateCallSiteField (site_type_decl, loc);
 459                         if (field == null)
 460                                 return;
 461
 462                         if (del_type_instance_access == null) {
 463                                 var dt = d.CurrentType.DeclaringType.MakeGenericType (module, context_mvars.Select (l => l.Type).ToArray ());
 464                                 del_type_instance_access = new TypeExpression (MemberCache.GetMember (dt, d.CurrentType), loc);
 465                         }
 466
 467                         var instanceAccessExprType = new GenericTypeExpr (module.PredefinedTypes.CallSiteGeneric.TypeSpec,
 468                                 new TypeArguments (del_type_instance_access), loc);
 469
 470                         if (instanceAccessExprType.ResolveAsType (ec.MemberContext) == null)
 471                                 return;
 472
 473                         bool inflate_using_mvar = context_mvars != null && ec.IsAnonymousStoreyMutateRequired;
 474
 475                         TypeSpec gt;
 476                         if (inflate_using_mvar || context_mvars == null) {
 477                                 gt = site_container.CurrentType;
 478                         } else {
 479                                 gt = site_container.CurrentType.MakeGenericType (module, context_mvars.Select (l => l.Type).ToArray ());
 480                         }
 481
 482                         // When site container already exists the inflated version has to be
 483                         // updated manually to contain newly created field
 484                         if (gt is InflatedTypeSpec && site_container.Fields.Count > 1) {
 485                                 var tparams = gt.MemberDefinition.TypeParametersCount > 0 ? gt.MemberDefinition.TypeParameters : TypeParameterSpec.EmptyTypes;
 486                                 var inflator = new TypeParameterInflator (module, gt, tparams, gt.TypeArguments);
 487                                 gt.MemberCache.AddMember (field.InflateMember (inflator));
 488                         }
 489
 490                         FieldExpr site_field_expr = new FieldExpr (MemberCache.GetMember (gt, field), loc);
 491
 492                         BlockContext bc = new BlockContext (ec.MemberContext, null, ec.BuiltinTypes.Void);
 493                         SymbolWriter.OpenCompilerGeneratedBlock (ec);
 494
 495                         Arguments args = new Arguments (1);
 496                         args.Add (new Argument (binder));
 497                         StatementExpression s = new StatementExpression (new SimpleAssign (site_field_expr, new Invocation (new MemberAccess (instanceAccessExprType, "Create"), args)));
 498
 499                         if (s.Resolve (bc)) {
 500                                 Statement init = new If (new Binary (Binary.Operator.Equality, site_field_expr, new NullLiteral (loc), loc), s, loc);
 501                                 init.Emit (ec);
 502                         }
 503
 504                         args = new Arguments (1 + dyn_args_count);
 505                         args.Add (new Argument (site_field_expr));
 506                         if (arguments != null) {
 507                                 int arg_pos = 1;
 508                                 foreach (Argument a in arguments) {
 509                                         if (a is NamedArgument) {
 510                                                 // Name is not valid in this context
 511                                                 args.Add (new Argument (a.Expr, a.ArgType));
 512                                         } else {
 513                                                 args.Add (a);
 514                                         }
 515
 516                                         if (inflate_using_mvar && a.Type != targs[arg_pos].Type)
 517                                                 a.Expr.Type = targs[arg_pos].Type;
 518
 519                                         ++arg_pos;
 520                                 }
 521                         }
 522
 523                         Expression target = new DelegateInvocation (new MemberAccess (site_field_expr, "Target", loc).Resolve (bc), args, loc).Resolve (bc);
 524                         if (target != null)
 525                                 target.Emit (ec);
 526
 527                         SymbolWriter.CloseCompilerGeneratedBlock (ec);
 528                 }
 529
 530                 public static MemberAccess GetBinderNamespace (Location loc)
 531                 {
 532                         return new MemberAccess (new MemberAccess (
 533                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "Microsoft", loc), "CSharp", loc), "RuntimeBinder", loc);
 534                 }
 535
 536                 protected MemberAccess GetBinder (string name, Location loc)
 537                 {
 538                         return new MemberAccess (new TypeExpression (binder_type, loc), name, loc);
 539                 }
 540         }
 541
 542         //
 543         // Dynamic member access compound assignment for events
 544         //
 545         class DynamicEventCompoundAssign : ExpressionStatement
 546         {
 547                 class IsEvent : DynamicExpressionStatement, IDynamicBinder
 548                 {
 549                         string name;
 550
 551                         public IsEvent (string name, Arguments args, Location loc)
 552                                 : base (null, args, loc)
 553                         {
 554                                 this.name = name;
 555                                 binder = this;
 556                         }
 557
 558                         public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 559                         {
 560                                 type = ec.BuiltinTypes.Bool;
 561
 562                                 Arguments binder_args = new Arguments (3);
 563
 564                                 binder_args.Add (new Argument (new BinderFlags (0, this)));
 565                                 binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, name, loc)));
 566                                 binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 567
 568                                 return new Invocation (GetBinder ("IsEvent", loc), binder_args);
 569                         }
 570                 }
 571
 572                 Expression condition;
 573                 ExpressionStatement invoke, assign;
 574
 575                 public DynamicEventCompoundAssign (string name, Arguments args, ExpressionStatement assignment, ExpressionStatement invoke, Location loc)
 576                 {
 577                         condition = new IsEvent (name, args, loc);
 578                         this.invoke = invoke;
 579                         this.assign = assignment;
 580                         this.loc = loc;
 581                 }
 582
 583                 public override Expression CreateExpressionTree (ResolveContext ec)
 584                 {
 585                         return condition.CreateExpressionTree (ec);
 586                 }
 587
 588                 protected override Expression DoResolve (ResolveContext rc)
 589                 {
 590                         type = rc.BuiltinTypes.Dynamic;
 591                         eclass = ExprClass.Value;
 592                         condition = condition.Resolve (rc);
 593                         return this;
 594                 }
 595
 596                 public override void Emit (EmitContext ec)
 597                 {
 598                         var rc = new ResolveContext (ec.MemberContext);
 599                         var expr = new Conditional (new BooleanExpression (condition), invoke, assign, loc).Resolve (rc);
 600                         expr.Emit (ec);
 601                 }
 602
 603                 public override void EmitStatement (EmitContext ec)
 604                 {
 605                         var stmt = new If (condition, new StatementExpression (invoke), new StatementExpression (assign), loc);
 606                         stmt.Emit (ec);
 607                 }
 608         }
 609
 610         class DynamicConversion : DynamicExpressionStatement, IDynamicBinder
 611         {
 612                 public DynamicConversion (TypeSpec targetType, CSharpBinderFlags flags, Arguments args, Location loc)
 613                         : base (null, args, loc)
 614                 {
 615                         type = targetType;
 616                         base.flags = flags;
 617                         base.binder = this;
 618                 }
 619
 620                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 621                 {
 622                         Arguments binder_args = new Arguments (3);
 623
 624                         flags |= ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
 625
 626                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 627                         binder_args.Add (new Argument (new TypeOf (type, loc)));
 628                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 629                         return new Invocation (GetBinder ("Convert", loc), binder_args);
 630                 }
 631         }
 632
 633         class DynamicConstructorBinder : DynamicExpressionStatement, IDynamicBinder
 634         {
 635                 public DynamicConstructorBinder (TypeSpec type, Arguments args, Location loc)
 636                         : base (null, args, loc)
 637                 {
 638                         this.type = type;
 639                         base.binder = this;
 640                 }
 641
 642                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 643                 {
 644                         Arguments binder_args = new Arguments (3);
 645
 646                         binder_args.Add (new Argument (new BinderFlags (0, this)));
 647                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 648                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
 649
 650                         return new Invocation (GetBinder ("InvokeConstructor", loc), binder_args);
 651                 }
 652         }
 653
 654         class DynamicIndexBinder : DynamicMemberAssignable
 655         {
 656                 bool can_be_mutator;
 657
 658                 public DynamicIndexBinder (Arguments args, Location loc)
 659                         : base (args, loc)
 660                 {
 661                 }
 662
 663                 public DynamicIndexBinder (CSharpBinderFlags flags, Arguments args, Location loc)
 664                         : this (args, loc)
 665                 {
 666                         base.flags = flags;
 667                 }
 668
 669                 protected override Expression DoResolve (ResolveContext ec)
 670                 {
 671                         can_be_mutator = true;
 672                         return base.DoResolve (ec);
 673                 }
 674
 675                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
 676                 {
 677                         Arguments binder_args = new Arguments (3);
 678
 679                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 680                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 681                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
 682
 683                         isSet |= (flags & CSharpBinderFlags.ValueFromCompoundAssignment) != 0;
 684                         return new Invocation (GetBinder (isSet ? "SetIndex" : "GetIndex", loc), binder_args);
 685                 }
 686
 687                 protected override Arguments CreateSetterArguments (ResolveContext rc, Expression rhs)
 688                 {
 689                         //
 690                         // Indexer has arguments which complicates things as the setter and getter
 691                         // are called in two steps when unary mutator is used. We have to make a
 692                         // copy of all variable arguments to not duplicate any side effect.
 693                         //
 694                         // ++d[++arg, Foo ()]
 695                         //
 696
 697                         if (!can_be_mutator)
 698                                 return base.CreateSetterArguments (rc, rhs);
 699
 700                         var setter_args = new Arguments (Arguments.Count + 1);
 701                         for (int i = 0; i < Arguments.Count; ++i) {
 702                                 var expr = Arguments[i].Expr;
 703
 704                                 if (expr is Constant || expr is VariableReference || expr is This) {
 705                                         setter_args.Add (Arguments [i]);
 706                                         continue;
 707                                 }
 708
 709                                 LocalVariable temp = LocalVariable.CreateCompilerGenerated (expr.Type, rc.CurrentBlock, loc);
 710                                 expr = new SimpleAssign (temp.CreateReferenceExpression (rc, expr.Location), expr).Resolve (rc);
 711                                 Arguments[i].Expr = temp.CreateReferenceExpression (rc, expr.Location).Resolve (rc);
 712                                 setter_args.Add (Arguments [i].Clone (expr));
 713                         }
 714
 715                         setter_args.Add (new Argument (rhs));
 716                         return setter_args;
 717                 }
 718         }
 719
 720         class DynamicInvocation : DynamicExpressionStatement, IDynamicBinder
 721         {
 722                 ATypeNameExpression member;
 723
 724                 public DynamicInvocation (ATypeNameExpression member, Arguments args, Location loc)
 725                         : base (null, args, loc)
 726                 {
 727                         base.binder = this;
 728                         this.member = member;
 729                 }
 730
 731                 //
 732                 // When a return type is known not to be dynamic
 733                 //
 734                 public DynamicInvocation (ATypeNameExpression member, Arguments args, TypeSpec type, Location loc)
 735                         : this (member, args, loc)
 736                 {
 737                         this.type = type;
 738                 }
 739
 740                 public static DynamicInvocation CreateSpecialNameInvoke (ATypeNameExpression member, Arguments args, Location loc)
 741                 {
 742                         return new DynamicInvocation (member, args, loc) {
 743                                 flags = CSharpBinderFlags.InvokeSpecialName
 744                         };
 745                 }
 746
 747                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 748                 {
 749                         Arguments binder_args = new Arguments (member != null ? 5 : 3);
 750                         bool is_member_access = member is MemberAccess;
 751
 752                         CSharpBinderFlags call_flags;
 753                         if (!is_member_access && member is SimpleName) {
 754                                 call_flags = CSharpBinderFlags.InvokeSimpleName;
 755                                 is_member_access = true;
 756                         } else {
 757                                 call_flags = 0;
 758                         }
 759
 760                         binder_args.Add (new Argument (new BinderFlags (call_flags, this)));
 761
 762                         if (is_member_access)
 763                                 binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, member.Name, member.Location)));
 764
 765                         if (member != null && member.HasTypeArguments) {
 766                                 TypeArguments ta = member.TypeArguments;
 767                                 if (ta.Resolve (ec)) {
 768                                         var targs = new ArrayInitializer (ta.Count, loc);
 769                                         foreach (TypeSpec t in ta.Arguments)
 770                                                 targs.Add (new TypeOf (t, loc));
 771
 772                                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (targs, loc)));
 773                                 }
 774                         } else if (is_member_access) {
 775                                 binder_args.Add (new Argument (new NullLiteral (loc)));
 776                         }
 777
 778                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 779
 780                         Expression real_args;
 781                         if (args == null) {
 782                                 // Cannot be null because .NET trips over
 783                                 real_args = new ArrayCreation (
 784                                         new MemberAccess (GetBinderNamespace (loc), "CSharpArgumentInfo", loc),
 785                                         new ArrayInitializer (0, loc), loc);
 786                         } else {
 787                                 real_args = new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc);
 788                         }
 789
 790                         binder_args.Add (new Argument (real_args));
 791
 792                         return new Invocation (GetBinder (is_member_access ? "InvokeMember" : "Invoke", loc), binder_args);
 793                 }
 794
 795                 public override void EmitStatement (EmitContext ec)
 796                 {
 797                         flags |= CSharpBinderFlags.ResultDiscarded;
 798                         base.EmitStatement (ec);
 799                 }
 800         }
 801
 802         class DynamicMemberBinder : DynamicMemberAssignable
 803         {
 804                 readonly string name;
 805
 806                 public DynamicMemberBinder (string name, Arguments args, Location loc)
 807                         : base (args, loc)
 808                 {
 809                         this.name = name;
 810                 }
 811
 812                 public DynamicMemberBinder (string name, CSharpBinderFlags flags, Arguments args, Location loc)
 813                         : this (name, args, loc)
 814                 {
 815                         base.flags = flags;
 816                 }
 817
 818                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
 819                 {
 820                         Arguments binder_args = new Arguments (4);
 821
 822                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 823                         binder_args.Add (new Argument (new StringLiteral (ec.BuiltinTypes, name, loc)));
 824                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 825                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
 826
 827                         isSet |= (flags & CSharpBinderFlags.ValueFromCompoundAssignment) != 0;
 828                         return new Invocation (GetBinder (isSet ? "SetMember" : "GetMember", loc), binder_args);
 829                 }
 830         }
 831
 832         //
 833         // Any member binder which can be source and target of assignment
 834         //
 835         abstract class DynamicMemberAssignable : DynamicExpressionStatement, IDynamicBinder, IAssignMethod
 836         {
 837                 Expression setter;
 838                 Arguments setter_args;
 839
 840                 protected DynamicMemberAssignable (Arguments args, Location loc)
 841                         : base (null, args, loc)
 842                 {
 843                         base.binder = this;
 844                 }
 845
 846                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 847                 {
 848                         //
 849                         // DoResolve always uses getter
 850                         //
 851                         return CreateCallSiteBinder (ec, args, false);
 852                 }
 853
 854                 protected abstract Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet);
 855
 856                 protected virtual Arguments CreateSetterArguments (ResolveContext rc, Expression rhs)
 857                 {
 858                         var setter_args = new Arguments (Arguments.Count + 1);
 859                         setter_args.AddRange (Arguments);
 860                         setter_args.Add (new Argument (rhs));
 861                         return setter_args;
 862                 }
 863
 864                 public override Expression DoResolveLValue (ResolveContext rc, Expression right_side)
 865                 {
 866                         if (right_side == EmptyExpression.OutAccess) {
 867                                 right_side.DoResolveLValue (rc, this);
 868                                 return null;
 869                         }
 870
 871                         if (DoResolveCore (rc)) {
 872                                 setter_args = CreateSetterArguments (rc, right_side);
 873                                 setter = CreateCallSiteBinder (rc, setter_args, true);
 874                         }
 875
 876                         eclass = ExprClass.Variable;
 877                         return this;
 878                 }
 879
 880                 public override void Emit (EmitContext ec)
 881                 {
 882                         // It's null for ResolveLValue used without assignment
 883                         if (binder_expr == null)
 884                                 EmitCall (ec, setter, Arguments, false);
 885                         else
 886                                 base.Emit (ec);
 887                 }
 888
 889                 public override void EmitStatement (EmitContext ec)
 890                 {
 891                         // It's null for ResolveLValue used without assignment
 892                         if (binder_expr == null)
 893                                 EmitCall (ec, setter, Arguments, true);
 894                         else
 895                                 base.EmitStatement (ec);
 896                 }
 897
 898                 #region IAssignMethod Members
 899
 900                 public void Emit (EmitContext ec, bool leave_copy)
 901                 {
 902                         throw new NotImplementedException ();
 903                 }
 904
 905                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool isCompound)
 906                 {
 907                         EmitCall (ec, setter, setter_args, !leave_copy);
 908                 }
 909
 910                 #endregion
 911         }
 912
 913         class DynamicUnaryConversion : DynamicExpressionStatement, IDynamicBinder
 914         {
 915                 readonly string name;
 916
 917                 public DynamicUnaryConversion (string name, Arguments args, Location loc)
 918                         : base (null, args, loc)
 919                 {
 920                         this.name = name;
 921                         base.binder = this;
 922                 }
 923
 924                 public static DynamicUnaryConversion CreateIsTrue (ResolveContext rc, Arguments args, Location loc)
 925                 {
 926                         return new DynamicUnaryConversion ("IsTrue", args, loc) { type = rc.BuiltinTypes.Bool };
 927                 }
 928
 929                 public static DynamicUnaryConversion CreateIsFalse (ResolveContext rc, Arguments args, Location loc)
 930                 {
 931                         return new DynamicUnaryConversion ("IsFalse", args, loc) { type = rc.BuiltinTypes.Bool };
 932                 }
 933
 934                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 935                 {
 936                         Arguments binder_args = new Arguments (4);
 937
 938                         MemberAccess sle = new MemberAccess (new MemberAccess (
 939                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Linq", loc), "Expressions", loc);
 940
 941                         var flags = ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
 942
 943                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 944                         binder_args.Add (new Argument (new MemberAccess (new MemberAccess (sle, "ExpressionType", loc), name, loc)));
 945                         binder_args.Add (new Argument (new TypeOf (ec.CurrentType, loc)));
 946                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation (args.CreateDynamicBinderArguments (ec), loc)));
 947
 948                         return new Invocation (GetBinder ("UnaryOperation", loc), binder_args);
 949                 }
 950         }
 951
 952         sealed class DynamicSiteClass : HoistedStoreyClass
 953         {
 954                 public DynamicSiteClass (TypeContainer parent, MemberBase host, TypeParameter[] tparams)
 955                         : base (parent, MakeMemberName (host, "DynamicSite", parent.DynamicSitesCounter, tparams, Location.Null), tparams, Modifiers.STATIC)
 956                 {
 957                         parent.DynamicSitesCounter++;
 958                 }
 959
 960                 public FieldSpec CreateCallSiteField (FullNamedExpression type, Location loc)
 961                 {
 962                         int index = fields == null ? 0 : fields.Count;
 963                         Field f = new HoistedField (this, type, Modifiers.PUBLIC | Modifiers.STATIC, "Site" + index.ToString ("X"), null, loc);
 964                         f.Define ();
 965
 966                         AddField (f);
 967                         return f.Spec;
 968                 }
 969         }
 970 }