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.Collections;
  13 using System.Reflection.Emit;
  14
  15 #if NET_4_0
  16 using System.Dynamic;
  17 using SLE = System.Linq.Expressions;
  18 #endif
  19
  20 namespace Mono.CSharp
  21 {
  22         //
  23         // A copy of Microsoft.CSharp/Microsoft.CSharp.RuntimeBinder/CSharpBinderFlags.cs
  24         // has to be kept in sync
  25         //
  26         [Flags]
  27         public enum CSharpBinderFlags
  28         {
  29                 None = 0,
  30                 CheckedContext = 1,
  31                 InvokeSimpleName = 1 << 1,
  32                 InvokeSpecialName = 1 << 2,
  33                 BinaryOperationLogical = 1 << 3,
  34                 ConvertExplicit = 1 << 4,
  35                 ConvertArrayIndex = 1 << 5,
  36                 ResultIndexed = 1 << 6,
  37                 ValueFromCompoundAssignment = 1 << 7,
  38                 ResultDiscarded = 1 << 8
  39         }
  40
  41         //
  42         // Type expression with internal dynamic type symbol
  43         //
  44         class DynamicTypeExpr : TypeExpr
  45         {
  46                 public DynamicTypeExpr (Location loc)
  47                 {
  48                         this.loc = loc;
  49
  50                         type = InternalType.Dynamic;
  51                         eclass = ExprClass.Type;
  52                 }
  53
  54                 public override bool CheckAccessLevel (IMemberContext ds)
  55                 {
  56                         return true;
  57                 }
  58
  59                 protected override TypeExpr DoResolveAsTypeStep (IMemberContext ec)
  60                 {
  61                         return this;
  62                 }
  63         }
  64
  65         #region Dynamic runtime binder expressions
  66
  67         //
  68         // Expression created from runtime dynamic object value by dynamic binder
  69         //
  70         public class RuntimeValueExpression : Expression, IDynamicAssign, IMemoryLocation
  71         {
  72 #if !NET_4_0
  73                 public class DynamicMetaObject
  74                 {
  75                         public Type RuntimeType;
  76                         public Type LimitType;
  77                 }
  78 #endif
  79
  80                 readonly DynamicMetaObject obj;
  81
  82                 public RuntimeValueExpression (DynamicMetaObject obj, bool isCompileTimeType)
  83                 {
  84                         this.obj = obj;
  85                         this.type = isCompileTimeType ? obj.LimitType : obj.RuntimeType;
  86                         this.type = obj.LimitType;
  87                         this.eclass = ExprClass.Variable;
  88                 }
  89
  90                 public void AddressOf (EmitContext ec, AddressOp mode)
  91                 {
  92                         throw new NotImplementedException ();
  93                 }
  94
  95                 public override Expression CreateExpressionTree (ResolveContext ec)
  96                 {
  97                         throw new NotImplementedException ();
  98                 }
  99
 100                 protected override Expression DoResolve (ResolveContext ec)
 101                 {
 102                         return this;
 103                 }
 104
 105                 public override Expression DoResolveLValue (ResolveContext ec, Expression right_side)
 106                 {
 107                         return this;
 108                 }
 109
 110                 public override void Emit (EmitContext ec)
 111                 {
 112                         throw new NotImplementedException ();
 113                 }
 114
 115                 #region IAssignMethod Members
 116
 117                 public void Emit (EmitContext ec, bool leave_copy)
 118                 {
 119                         throw new NotImplementedException ();
 120                 }
 121
 122                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
 123                 {
 124                         throw new NotImplementedException ();
 125                 }
 126
 127                 #endregion
 128
 129 #if NET_4_0
 130                 public SLE.Expression MakeAssignExpression (BuilderContext ctx)
 131                 {
 132                         return obj.Expression;
 133                 }
 134
 135                 public override SLE.Expression MakeExpression (BuilderContext ctx)
 136                 {
 137                         return SLE.Expression.Convert (obj.Expression, type);
 138                 }
 139 #endif
 140
 141                 public DynamicMetaObject MetaObject {
 142                         get { return obj; }
 143                 }
 144         }
 145
 146         //
 147         // Wraps runtime dynamic expression into expected type. Needed
 148         // to satify expected type check by dynamic binder and no conversion
 149         // is required (ResultDiscarded).
 150         //
 151         public class DynamicResultCast : ShimExpression
 152         {
 153                 public DynamicResultCast (Type type, Expression expr)
 154                         : base (expr)
 155                 {
 156                         this.type = type;
 157                 }
 158
 159                 protected override Expression DoResolve (ResolveContext ec)
 160                 {
 161                         expr = expr.Resolve (ec);
 162                         eclass = ExprClass.Value;
 163                         return this;
 164                 }
 165
 166 #if NET_4_0
 167                 public override SLE.Expression MakeExpression (BuilderContext ctx)
 168                 {
 169                         return SLE.Expression.Block (expr.MakeExpression (ctx), SLE.Expression.Default (type));
 170                 }
 171 #endif
 172         }
 173
 174         #endregion
 175
 176         //
 177         // Creates dynamic binder expression
 178         //
 179         interface IDynamicBinder
 180         {
 181                 Expression CreateCallSiteBinder (ResolveContext ec, Arguments args);
 182         }
 183
 184         //
 185         // Extends standard assignment interface for expressions
 186         // supported by dynamic resolver
 187         //
 188         interface IDynamicAssign : IAssignMethod
 189         {
 190 #if NET_4_0
 191                 SLE.Expression MakeAssignExpression (BuilderContext ctx);
 192 #endif
 193         }
 194
 195         //
 196         // Base dynamic expression statement creator
 197         //
 198         class DynamicExpressionStatement : ExpressionStatement
 199         {
 200                 class StaticDataClass : CompilerGeneratedClass
 201                 {
 202                         public StaticDataClass ()
 203                                 : base (new RootDeclSpace (new NamespaceEntry (null, null, null)),
 204                                         new MemberName (CompilerGeneratedClass.MakeName (null, "c", "DynamicSites", 0)),
 205                                         Modifiers.INTERNAL | Modifiers.STATIC)
 206                         {
 207                                 ModFlags &= ~Modifiers.SEALED;
 208                         }
 209                 }
 210
 211                 //
 212                 // Binder flag dynamic constant, the value is combination of
 213                 // flags known at resolve stage and flags known only at emit
 214                 // stage
 215                 //
 216                 protected class BinderFlags : EnumConstant
 217                 {
 218                         DynamicExpressionStatement statement;
 219                         CSharpBinderFlags flags;
 220
 221                         public BinderFlags (CSharpBinderFlags flags, DynamicExpressionStatement statement)
 222                                 : base (statement.loc)
 223                         {
 224                                 this.flags = flags;
 225                                 this.statement = statement;
 226                         }
 227
 228                         protected override Expression DoResolve (ResolveContext ec)
 229                         {
 230                                 Child = new IntConstant ((int) (flags | statement.flags), statement.loc).Resolve (ec);
 231
 232                                 type = TypeManager.binder_flags;
 233                                 eclass = Child.eclass;
 234                                 return this;
 235                         }
 236                 }
 237
 238                 static StaticDataClass global_site_container;
 239                 static int field_counter;
 240                 static int container_counter;
 241
 242                 readonly Arguments arguments;
 243                 protected IDynamicBinder binder;
 244                 protected Expression binder_expr;
 245
 246                 // Used by BinderFlags
 247                 protected CSharpBinderFlags flags;
 248
 249                 public DynamicExpressionStatement (IDynamicBinder binder, Arguments args, Location loc)
 250                 {
 251                         this.binder = binder;
 252                         this.arguments = args;
 253                         this.loc = loc;
 254                 }
 255
 256                 public Arguments Arguments {
 257                         get {
 258                                 return arguments;
 259                         }
 260                 }
 261
 262                 static TypeContainer CreateSiteContainer ()
 263                 {
 264                         if (global_site_container == null) {
 265                                 global_site_container = new StaticDataClass ();
 266                                 RootContext.ToplevelTypes.AddCompilerGeneratedClass (global_site_container);
 267                                 global_site_container.DefineType ();
 268                                 global_site_container.Define ();
 269 //                              global_site_container.EmitType ();
 270
 271                                 RootContext.RegisterCompilerGeneratedType (global_site_container.TypeBuilder);
 272                         }
 273
 274                         return global_site_container;
 275                 }
 276
 277                 static Field CreateSiteField (FullNamedExpression type)
 278                 {
 279                         TypeContainer site_container = CreateSiteContainer ();
 280                         Field f = new Field (site_container, type, Modifiers.PUBLIC | Modifiers.STATIC,
 281                                 new MemberName ("Site" +  field_counter++), null);
 282                         f.Define ();
 283
 284                         site_container.AddField (f);
 285                         return f;
 286                 }
 287
 288                 public override Expression CreateExpressionTree (ResolveContext ec)
 289                 {
 290                         ec.Report.Error (1963, loc, "An expression tree cannot contain a dynamic operation");
 291                         return null;
 292                 }
 293
 294                 protected override Expression DoResolve (ResolveContext ec)
 295                 {
 296                         if (DoResolveCore (ec))
 297                                 binder_expr = binder.CreateCallSiteBinder (ec, arguments);
 298
 299                         return this;
 300                 }
 301
 302                 protected bool DoResolveCore (ResolveContext rc)
 303                 {
 304                         int errors = rc.Report.Errors;
 305
 306                         if (TypeManager.binder_type == null) {
 307                                 var t = TypeManager.CoreLookupType (rc.Compiler,
 308                                         "Microsoft.CSharp.RuntimeBinder", "Binder", Kind.Class, true);
 309                                 if (t != null)
 310                                         TypeManager.binder_type = new TypeExpression (t, Location.Null);
 311                         }
 312
 313                         if (TypeManager.call_site_type == null)
 314                                 TypeManager.call_site_type = TypeManager.CoreLookupType (rc.Compiler,
 315                                         "System.Runtime.CompilerServices", "CallSite", Kind.Class, true);
 316
 317                         if (TypeManager.generic_call_site_type == null)
 318                                 TypeManager.generic_call_site_type = TypeManager.CoreLookupType (rc.Compiler,
 319                                         "System.Runtime.CompilerServices", "CallSite`1", Kind.Class, true);
 320
 321                         if (TypeManager.binder_flags == null) {
 322                                 TypeManager.binder_flags = TypeManager.CoreLookupType (rc.Compiler,
 323                                         "Microsoft.CSharp.RuntimeBinder", "CSharpBinderFlags", Kind.Enum, true);
 324                         }
 325
 326                         eclass = ExprClass.Value;
 327
 328                         if (type == null)
 329                                 type = InternalType.Dynamic;
 330
 331                         if (rc.Report.Errors == errors)
 332                                 return true;
 333
 334                         rc.Report.Error (1969, loc,
 335                                 "Dynamic operation cannot be compiled without `Microsoft.CSharp.dll' assembly reference");
 336                         return false;
 337                 }
 338
 339                 public override void Emit (EmitContext ec)
 340                 {
 341                         EmitCall (ec, binder_expr, arguments,  false);
 342                 }
 343
 344                 public override void EmitStatement (EmitContext ec)
 345                 {
 346                         EmitCall (ec, binder_expr, arguments, true);
 347                 }
 348
 349                 protected void EmitCall (EmitContext ec, Expression binder, Arguments arguments, bool isStatement)
 350                 {
 351                         int dyn_args_count = arguments == null ? 0 : arguments.Count;
 352                         TypeExpr site_type = CreateSiteType (RootContext.ToplevelTypes.Compiler, arguments, dyn_args_count, isStatement);
 353                         FieldExpr site_field_expr = new FieldExpr (CreateSiteField (site_type).FieldBuilder, loc);
 354
 355                         SymbolWriter.OpenCompilerGeneratedBlock (ec.ig);
 356
 357                         Arguments args = new Arguments (1);
 358                         args.Add (new Argument (binder));
 359                         StatementExpression s = new StatementExpression (new SimpleAssign (site_field_expr, new Invocation (new MemberAccess (site_type, "Create"), args)));
 360
 361                         BlockContext bc = new BlockContext (ec.MemberContext, null, TypeManager.void_type);
 362                         if (s.Resolve (bc)) {
 363                                 Statement init = new If (new Binary (Binary.Operator.Equality, site_field_expr, new NullLiteral (loc)), s, loc);
 364                                 init.Emit (ec);
 365                         }
 366
 367                         args = new Arguments (1 + dyn_args_count);
 368                         args.Add (new Argument (site_field_expr));
 369                         if (arguments != null) {
 370                                 foreach (Argument a in arguments) {
 371                                         if (a is NamedArgument) {
 372                                                 // Name is not valid in this context
 373                                                 args.Add (new Argument (a.Expr, a.ArgType));
 374                                                 continue;
 375                                         }
 376
 377                                         args.Add (a);
 378                                 }
 379                         }
 380
 381                         Expression target = new DelegateInvocation (new MemberAccess (site_field_expr, "Target", loc).Resolve (bc), args, loc).Resolve (bc);
 382                         if (target != null)
 383                                 target.Emit (ec);
 384
 385                         SymbolWriter.CloseCompilerGeneratedBlock (ec.ig);
 386                 }
 387
 388                 public static MemberAccess GetBinderNamespace (Location loc)
 389                 {
 390                         return new MemberAccess (new MemberAccess (
 391                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "Microsoft", loc), "CSharp", loc), "RuntimeBinder", loc);
 392                 }
 393
 394                 public static MemberAccess GetBinder (string name, Location loc)
 395                 {
 396                         return new MemberAccess (TypeManager.binder_type, name, loc);
 397                 }
 398
 399                 TypeExpr CreateSiteType (CompilerContext ctx, Arguments arguments, int dyn_args_count, bool is_statement)
 400                 {
 401                         int default_args = is_statement ? 1 : 2;
 402
 403                         bool has_ref_out_argument = false;
 404                         FullNamedExpression[] targs = new FullNamedExpression[dyn_args_count + default_args];
 405                         targs [0] = new TypeExpression (TypeManager.call_site_type, loc);
 406                         for (int i = 0; i < dyn_args_count; ++i) {
 407                                 Type arg_type;
 408                                 Argument a = arguments [i];
 409                                 if (a.Type == TypeManager.null_type)
 410                                         arg_type = TypeManager.object_type;
 411                                 else
 412                                         arg_type = a.Type;
 413
 414                                 if (a.ArgType == Argument.AType.Out || a.ArgType == Argument.AType.Ref)
 415                                         has_ref_out_argument = true;
 416
 417                                 targs [i + 1] = new TypeExpression (arg_type, loc);
 418                         }
 419
 420                         TypeExpr del_type = null;
 421                         if (!has_ref_out_argument) {
 422                                 string d_name = is_statement ? "Action`" : "Func`";
 423
 424                                 Type t = TypeManager.CoreLookupType (ctx, "System", d_name + (dyn_args_count + default_args), Kind.Delegate, false);
 425                                 if (t != null) {
 426                                         if (!is_statement)
 427                                                 targs [targs.Length - 1] = new TypeExpression (type, loc);
 428
 429                                         del_type = new GenericTypeExpr (t, new TypeArguments (targs), loc);
 430                                 }
 431                         }
 432
 433                         //
 434                         // Create custom delegate when no appropriate predefined one is found
 435                         //
 436                         if (del_type == null) {
 437                                 Type rt = is_statement ? TypeManager.void_type : type;
 438                                 Parameter[] p = new Parameter [dyn_args_count + 1];
 439                                 p[0] = new Parameter (targs [0], "p0", Parameter.Modifier.NONE, null, loc);
 440
 441                                 for (int i = 1; i < dyn_args_count + 1; ++i)
 442                                         p[i] = new Parameter (targs[i], "p" + i.ToString ("X"), arguments[i - 1].Modifier, null, loc);
 443
 444                                 TypeContainer parent = CreateSiteContainer ();
 445                                 Delegate d = new Delegate (parent.NamespaceEntry, parent, new TypeExpression (rt, loc),
 446                                         Modifiers.INTERNAL | Modifiers.COMPILER_GENERATED,
 447                                         new MemberName ("Container" + container_counter++.ToString ("X")),
 448                                         new ParametersCompiled (ctx, p), null);
 449
 450                                 d.DefineType ();
 451                                 d.Define ();
 452
 453                                 parent.AddDelegate (d);
 454                                 del_type = new TypeExpression (d.TypeBuilder, loc);
 455                         }
 456
 457                         TypeExpr site_type = new GenericTypeExpr (TypeManager.generic_call_site_type, new TypeArguments (del_type), loc);
 458                         return site_type;
 459                 }
 460
 461                 public static void Reset ()
 462                 {
 463                         global_site_container = null;
 464                         field_counter = container_counter = 0;
 465                 }
 466         }
 467
 468         //
 469         // Dynamic member access compound assignment for events
 470         //
 471         class DynamicEventCompoundAssign : DynamicExpressionStatement, IDynamicBinder
 472         {
 473                 string name;
 474                 Statement condition;
 475
 476                 public DynamicEventCompoundAssign (string name, Arguments args, ExpressionStatement assignment, ExpressionStatement invoke, Location loc)
 477                         : base (null, args, loc)
 478                 {
 479                         this.name = name;
 480                         base.binder = this;
 481
 482                         // Used by += or -= only
 483                         type = TypeManager.bool_type;
 484
 485                         condition = new If (
 486                                 new Binary (Binary.Operator.Equality, this, new BoolLiteral (true, loc)),
 487                                 new StatementExpression (invoke), new StatementExpression (assignment),
 488                                 loc);
 489                 }
 490
 491                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 492                 {
 493                         Arguments binder_args = new Arguments (3);
 494
 495                         binder_args.Add (new Argument (new BinderFlags (0, this)));
 496                         binder_args.Add (new Argument (new StringLiteral (name, loc)));
 497                         binder_args.Add (new Argument (new TypeOf (new TypeExpression (ec.CurrentType, loc), loc)));
 498
 499                         return new Invocation (GetBinder ("IsEvent", loc), binder_args);
 500                 }
 501
 502                 public override void EmitStatement (EmitContext ec)
 503                 {
 504                         condition.Emit (ec);
 505                 }
 506         }
 507
 508         class DynamicConversion : DynamicExpressionStatement, IDynamicBinder
 509         {
 510                 public DynamicConversion (Type targetType, CSharpBinderFlags flags, Arguments args, Location loc)
 511                         : base (null, args, loc)
 512                 {
 513                         type = targetType;
 514                         base.flags = flags;
 515                         base.binder = this;
 516                 }
 517
 518                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 519                 {
 520                         Arguments binder_args = new Arguments (2);
 521
 522                         flags |= ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
 523
 524                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 525                         binder_args.Add (new Argument (new TypeOf (new TypeExpression (type, loc), loc)));
 526                         return new Invocation (GetBinder ("Convert", loc), binder_args);
 527                 }
 528         }
 529
 530         class DynamicConstructorBinder : DynamicExpressionStatement, IDynamicBinder
 531         {
 532                 public DynamicConstructorBinder (Type type, Arguments args, Location loc)
 533                         : base (null, args, loc)
 534                 {
 535                         this.type = type;
 536                         base.binder = this;
 537                 }
 538
 539                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 540                 {
 541                         Arguments binder_args = new Arguments (3);
 542
 543                         binder_args.Add (new Argument (new BinderFlags (0, this)));
 544                         binder_args.Add (new Argument (new TypeOf (new TypeExpression (ec.CurrentType, loc), loc)));
 545                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation ("[]", args.CreateDynamicBinderArguments (ec), loc)));
 546
 547                         return new Invocation (GetBinder ("InvokeConstructor", loc), binder_args);
 548                 }
 549         }
 550
 551         class DynamicIndexBinder : DynamicMemberAssignable
 552         {
 553                 public DynamicIndexBinder (Arguments args, Location loc)
 554                         : base (args, loc)
 555                 {
 556                 }
 557
 558                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
 559                 {
 560                         Arguments binder_args = new Arguments (3);
 561
 562                         binder_args.Add (new Argument (new BinderFlags (0, this)));
 563                         binder_args.Add (new Argument (new TypeOf (new TypeExpression (ec.CurrentType, loc), loc)));
 564                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation ("[]", args.CreateDynamicBinderArguments (ec), loc)));
 565
 566                         return new Invocation (GetBinder (isSet ? "SetIndex" : "GetIndex", loc), binder_args);
 567                 }
 568         }
 569
 570         class DynamicInvocation : DynamicExpressionStatement, IDynamicBinder
 571         {
 572                 ATypeNameExpression member;
 573
 574                 public DynamicInvocation (ATypeNameExpression member, Arguments args, Location loc)
 575                         : base (null, args, loc)
 576                 {
 577                         base.binder = this;
 578                         this.member = member;
 579                 }
 580
 581                 public DynamicInvocation (ATypeNameExpression member, Arguments args, Type type, Location loc)
 582                         : this (member, args, loc)
 583                 {
 584                         // When a return type is known not to be dynamic
 585                         this.type = type;
 586                 }
 587
 588                 public static DynamicInvocation CreateSpecialNameInvoke (ATypeNameExpression member, Arguments args, Location loc)
 589                 {
 590                         return new DynamicInvocation (member, args, loc) {
 591                                 flags = CSharpBinderFlags.InvokeSpecialName
 592                         };
 593                 }
 594
 595                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 596                 {
 597                         Arguments binder_args = new Arguments (member != null ? 5 : 3);
 598                         bool is_member_access = member is MemberAccess;
 599
 600                         CSharpBinderFlags call_flags;
 601                         if (!is_member_access && member is SimpleName) {
 602                                 call_flags = CSharpBinderFlags.InvokeSimpleName;
 603                                 is_member_access = true;
 604                         } else {
 605                                 call_flags = 0;
 606                         }
 607
 608                         binder_args.Add (new Argument (new BinderFlags (call_flags, this)));
 609
 610                         if (is_member_access)
 611                                 binder_args.Add (new Argument (new StringLiteral (member.Name, member.Location)));
 612
 613                         if (member != null && member.HasTypeArguments) {
 614                                 TypeArguments ta = member.TypeArguments;
 615                                 if (ta.Resolve (ec)) {
 616                                         ArrayList targs = new ArrayList (ta.Count);
 617                                         foreach (Type t in ta.Arguments)
 618                                                 targs.Add (new TypeOf (new TypeExpression (t, loc), loc));
 619
 620                                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation ("[]", targs, loc)));
 621                                 }
 622                         } else if (is_member_access) {
 623                                 binder_args.Add (new Argument (new NullLiteral (loc)));
 624                         }
 625
 626                         binder_args.Add (new Argument (new TypeOf (new TypeExpression (ec.CurrentType, loc), loc)));
 627
 628                         Expression real_args;
 629                         if (args == null) {
 630                                 // Cannot be null because .NET trips over
 631                                 real_args = new ArrayCreation (new MemberAccess (GetBinderNamespace (loc), "CSharpArgumentInfo", loc), "[]", new ArrayList (0), loc);
 632                         } else {
 633                                 real_args = new ImplicitlyTypedArrayCreation ("[]", args.CreateDynamicBinderArguments (ec), loc);
 634                         }
 635
 636                         binder_args.Add (new Argument (real_args));
 637
 638                         return new Invocation (GetBinder (is_member_access ? "InvokeMember" : "Invoke", loc), binder_args);
 639                 }
 640
 641                 public override void EmitStatement (EmitContext ec)
 642                 {
 643                         flags |= CSharpBinderFlags.ResultDiscarded;
 644                         base.EmitStatement (ec);
 645                 }
 646         }
 647
 648         class DynamicMemberBinder : DynamicMemberAssignable
 649         {
 650                 readonly string name;
 651
 652                 public DynamicMemberBinder (string name, Arguments args, Location loc)
 653                         : base (args, loc)
 654                 {
 655                         this.name = name;
 656                 }
 657
 658                 protected override Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet)
 659                 {
 660                         Arguments binder_args = new Arguments (4);
 661
 662                         binder_args.Add (new Argument (new BinderFlags (0, this)));
 663                         binder_args.Add (new Argument (new StringLiteral (name, loc)));
 664                         binder_args.Add (new Argument (new TypeOf (new TypeExpression (ec.CurrentType, loc), loc)));
 665                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation ("[]", args.CreateDynamicBinderArguments (ec), loc)));
 666
 667                         return new Invocation (GetBinder (isSet ? "SetMember" : "GetMember", loc), binder_args);
 668                 }
 669         }
 670
 671         //
 672         // Any member binder which can be source and target of assignment
 673         //
 674         abstract class DynamicMemberAssignable : DynamicExpressionStatement, IDynamicBinder, IAssignMethod
 675         {
 676                 Expression setter;
 677                 Arguments setter_args;
 678
 679                 protected DynamicMemberAssignable (Arguments args, Location loc)
 680                         : base (null, args, loc)
 681                 {
 682                         base.binder = this;
 683                 }
 684
 685                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 686                 {
 687                         //
 688                         // DoResolve always uses getter
 689                         //
 690                         return CreateCallSiteBinder (ec, args, false);
 691                 }
 692
 693                 protected abstract Expression CreateCallSiteBinder (ResolveContext ec, Arguments args, bool isSet);
 694
 695                 public override Expression DoResolveLValue (ResolveContext rc, Expression right_side)
 696                 {
 697                         if (right_side == EmptyExpression.OutAccess.Instance) {
 698                                 right_side.DoResolveLValue (rc, this);
 699                                 return null;
 700                         }
 701
 702                         if (DoResolveCore (rc)) {
 703                                 setter_args = new Arguments (Arguments.Count + 1);
 704                                 setter_args.AddRange (Arguments);
 705                                 setter_args.Add (new Argument (right_side));
 706                                 setter = CreateCallSiteBinder (rc, setter_args, true);
 707                         }
 708
 709                         eclass = ExprClass.Variable;
 710                         return this;
 711                 }
 712
 713                 public override void Emit (EmitContext ec)
 714                 {
 715                         // It's null for ResolveLValue used without assignment
 716                         if (binder_expr == null)
 717                                 EmitCall (ec, setter, Arguments, false);
 718                         else
 719                                 base.Emit (ec);
 720                 }
 721
 722                 public override void EmitStatement (EmitContext ec)
 723                 {
 724                         // It's null for ResolveLValue used without assignment
 725                         if (binder_expr == null)
 726                                 EmitCall (ec, setter, Arguments, true);
 727                         else
 728                                 base.EmitStatement (ec);
 729                 }
 730
 731                 #region IAssignMethod Members
 732
 733                 public void Emit (EmitContext ec, bool leave_copy)
 734                 {
 735                         throw new NotImplementedException ();
 736                 }
 737
 738                 public void EmitAssign (EmitContext ec, Expression source, bool leave_copy, bool prepare_for_load)
 739                 {
 740                         EmitCall (ec, setter, setter_args, !leave_copy);
 741                 }
 742
 743                 #endregion
 744         }
 745
 746         class DynamicUnaryConversion : DynamicExpressionStatement, IDynamicBinder
 747         {
 748                 string name;
 749
 750                 public DynamicUnaryConversion (string name, Arguments args, Location loc)
 751                         : base (null, args, loc)
 752                 {
 753                         this.name = name;
 754                         base.binder = this;
 755                         if (name == "IsTrue" || name == "IsFalse")
 756                                 type = TypeManager.bool_type;
 757                 }
 758
 759                 public Expression CreateCallSiteBinder (ResolveContext ec, Arguments args)
 760                 {
 761                         Arguments binder_args = new Arguments (3);
 762
 763                         MemberAccess sle = new MemberAccess (new MemberAccess (
 764                                 new QualifiedAliasMember (QualifiedAliasMember.GlobalAlias, "System", loc), "Linq", loc), "Expressions", loc);
 765
 766                         var flags = ec.HasSet (ResolveContext.Options.CheckedScope) ? CSharpBinderFlags.CheckedContext : 0;
 767
 768                         binder_args.Add (new Argument (new BinderFlags (flags, this)));
 769                         binder_args.Add (new Argument (new MemberAccess (new MemberAccess (sle, "ExpressionType", loc), name, loc)));
 770                         binder_args.Add (new Argument (new ImplicitlyTypedArrayCreation ("[]", args.CreateDynamicBinderArguments (ec), loc)));
 771
 772                         return new Invocation (GetBinder ("UnaryOperation", loc), binder_args);
 773                 }
 774         }
 775 }