Things to do for the REPL support in MCS: Documentation for the REPL mode for MCS can be found here: http://mono-project.com/CsharpRepl * Embedding API * Booting the compiler without Main () * Expose LoadAssembly/LoadPackage * Register fields? * Register a lookup function for fields? * Register classes to expose to REPL * Embedded Library * Run a REPL on a socket (from Joe Shaw) * Host a REPL on XSP (from Nat). * TODO Clear struct fields inside the clearing code. * Other ideas: MD addin for "csharp" * Supporting class-level declarations Currently the evaluator has this feature disabled, to enable it edit the eval.cs file and make this be the default: - parser.Lexer.putback_char = Tokenizer.EvalUsingDeclarationsParserCharacter; - //parser.Lexer.putback_char = Tokenizer.EvalCompilationUnitParserCharacter; + //parser.Lexer.putback_char = Tokenizer.EvalUsingDeclarationsParserCharacter; + parser.Lexer.putback_char = Tokenizer.EvalCompilationUnitParserCharacter; It currently has a few problems: * Support for overwritting existing defined classes is not supported. * The usability is not as useful, since the defaults for C# are still to make members private, we should change this default to be public in those cases. * The error lookup system lacks information from types, for example this causes an unsupported call into a TypeBuilder: csharp>class D { void DD () {} } csharp>var d = new D (); csharp>d.DD (); Internal compiler error at Internal(1,1):: exception caught while emitting MethodBuilder [Class0::Host] System.NotSupportedException: The invoked member is not supported in a dynamic module. at System.Reflection.Emit.AssemblyBuilder.get_Location () [0x00000] in :0 at Mono.CSharp.Report.SymbolRelatedToPreviousError (System.Reflection.MemberInfo mi) [0x00000] in at Mono.CSharp.MethodGroupExpr.NoExactMatch (Mono.CSharp.ResolveContext ec, Mono.CSharp.Arguments& Arguments, IDictionary`2 c The above is caused by TypeManager.LookupDeclSpace (dt) failing to return a value (it returns null) so our code assumes we have an Assembly instead of an assemblybuilder. * Declaring a class twice produces an internal parse error: class X {} class X {} The second declaration will no longer be parsed, so it could even contain junk, and wont be flagged. We probably need to allow for type redefinition in REPL modes, the exception from the second is: csharp -v -v > class X {} > class X {} System.ArgumentException: An element with the same key already exists in the dictionary. at System.Collections.Generic.Dictionary`2[System.String,Mono.CSharp.DeclSpace].Add (System.String key, Mono.CSharp.DeclSpace value) [0x00000] in :0 at Mono.CSharp.Namespace.AddDeclSpace (System.String name, Mono.CSharp.DeclSpace ds) [0x00000] in :0 at Mono.CSharp.ModuleCompiled.AddMemberType (Mono.CSharp.DeclSpace ds) [0x00000] in :0 at Mono.CSharp.TypeContainer.AddTypeContainer (Mono.CSharp.TypeContainer tc) [0x00000] in :0 at Mono.CSharp.CSharpParser.push_current_class (Mono.CSharp.TypeContainer tc, System.Object partial_token) [0x00000] in :0 at Mono.CSharp.CSharpParser.yyparse (yyInput yyLex) [0x00000] in :0 at Mono.CSharp.CSharpParser.yyparse (yyInput yyLex, System.Object yyd) [0x00000] in :0 at Mono.CSharp.CSharpParser.parse () [0x00000] in :0 * Mix statements with other top-level declarations. csharp> class Y {static void Main () {Console.WriteLine ("Foo"); }} csharp> typeof (Y); Y csharp> Y.Main (); Exception caught by the compiler while compiling: Block that caused the problem begin at: Internal(1,1): Block being compiled: [(1,2):,(1,11):] System.NotSupportedException: The invoked member is not supported in a dynamic module. Internal compiler error at Internal(1,1):: exception caught while emitting MethodBuilder [Class2::Host] System.NotSupportedException: The invoked member is not supported in a dynamic module. at System.Reflection.Emit.AssemblyBuilder.get_Location () [0x00000] in /second/home/cvs/mcs/class/corlib/System.Reflection.Emit/AssemblyBuilder.cs:214 at Mono.CSharp.Report.SymbolRelatedToPreviousError (System.Reflection.MemberInfo mi) [0x00036] in /second/home/cvs/mcs/mcs/report.cs:664 at Mono.CSharp.Expression.Error_MemberLookupFailed (System.Type container_type, System.Type qualifier_type, System.Type queried_type, System.String name, System.String class_name, MemberTypes mt, BindingFlags bf) [0x00121] in /second/home/cvs/mcs/mcs/ecore.cs:857 at Mono.CSharp.MemberAccess.DoResolve (Mono.CSharp.EmitContext ec, Mono.CSharp.Expression right_side) [0x00230] in /second/home/cvs/mcs/mcs/expression.cs:7426 at Mono.CSharp.MemberAccess.DoResolve (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/expression.cs:7494 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec, ResolveFlags flags) [0x00075] in /second/home/cvs/mcs/mcs/ecore.cs:479 at Mono.CSharp.Invocation.DoResolve (Mono.CSharp.EmitContext ec) [0x0000d] in /second/home/cvs/mcs/mcs/expression.cs:4725 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec, ResolveFlags flags) [0x00075] in /second/home/cvs/mcs/mcs/ecore.cs:479 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/ecore.cs:506 at Mono.CSharp.OptionalAssign.DoResolve (Mono.CSharp.EmitContext ec) [0x00013] in /second/home/cvs/mcs/mcs/repl.cs:681 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec, ResolveFlags flags) [0x00075] in /second/home/cvs/mcs/mcs/ecore.cs:479 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/ecore.cs:506 at Mono.CSharp.ExpressionStatement.ResolveStatement (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/ecore.cs:1307 at Mono.CSharp.StatementExpression.Resolve (Mono.CSharp.EmitContext ec) [0x0000b] in /second/home/cvs/mcs/mcs/statement.cs:743 at Mono.CSharp.Block.Resolve (Mono.CSharp.EmitContext ec) [0x000f0] in /second/home/cvs/mcs/mcs/statement.cs:2254 at Mono.CSharp.ExplicitBlock.Resolve (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/statement.cs:2550 at Mono.CSharp.EmitContext.ResolveTopBlock (Mono.CSharp.EmitContext anonymous_method_host, Mono.CSharp.ToplevelBlock block, Mono.CSharp.Parameters ip, IMethodData md, System.Boolean& unreachable) [0x00087] in /second/home/cvs/mcs/mcs/codegen.cs:796 csharp> * Another one: csharp> class X { X (){ Console.WriteLine ("Called"); } } csharp> new X (); Exception caught by the compiler while compiling: Block that caused the problem begin at: Internal(1,1): Block being compiled: [(1,2):,(1,10):] System.NotSupportedException: The invoked member is not supported in a dynamic module. Internal compiler error at Internal(1,1):: exception caught while emitting MethodBuilder [Class0::Host] System.NotSupportedException: The invoked member is not supported in a dynamic module. at System.Reflection.Emit.AssemblyBuilder.get_Location () [0x00000] in /second/home/cvs/mcs/class/corlib/System.Reflection.Emit/AssemblyBuilder.cs:214 at Mono.CSharp.Report.SymbolRelatedToPreviousError (System.Reflection.MemberInfo mi) [0x00036] in /second/home/cvs/mcs/mcs/report.cs:664 at Mono.CSharp.Expression.Error_MemberLookupFailed (System.Type container_type, System.Type qualifier_type, System.Type queried_type, System.String name, System.String class_name, MemberTypes mt, BindingFlags bf) [0x00121] in /second/home/cvs/mcs/mcs/ecore.cs:857 at Mono.CSharp.Expression.MemberLookupFinal (Mono.CSharp.EmitContext ec, System.Type qualifier_type, System.Type queried_type, System.String name, MemberTypes mt, BindingFlags bf, Location loc) [0x0002f] in /second/home/cvs/mcs/mcs/ecore.cs:804 at Mono.CSharp.New.DoResolve (Mono.CSharp.EmitContext ec) [0x002ad] in /second/home/cvs/mcs/mcs/expression.cs:5486 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec, ResolveFlags flags) [0x00075] in /second/home/cvs/mcs/mcs/ecore.cs:479 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/ecore.cs:506 at Mono.CSharp.OptionalAssign.DoResolve (Mono.CSharp.EmitContext ec) [0x00013] in /second/home/cvs/mcs/mcs/repl.cs:687 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec, ResolveFlags flags) [0x00075] in /second/home/cvs/mcs/mcs/ecore.cs:479 at Mono.CSharp.Expression.Resolve (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/ecore.cs:506 at Mono.CSharp.ExpressionStatement.ResolveStatement (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/ecore.cs:1307 at Mono.CSharp.StatementExpression.Resolve (Mono.CSharp.EmitContext ec) [0x0000b] in /second/home/cvs/mcs/mcs/statement.cs:743 at Mono.CSharp.Block.Resolve (Mono.CSharp.EmitContext ec) [0x000f0] in /second/home/cvs/mcs/mcs/statement.cs:2254 at Mono.CSharp.ExplicitBlock.Resolve (Mono.CSharp.EmitContext ec) [0x00000] in /second/home/cvs/mcs/mcs/statement.cs:2550 at Mono.CSharp.EmitContext.ResolveTopBlock (Mono.CSharp.EmitContext anonymous_method_host, Mono.CSharp.ToplevelBlock block, Mono.CSharp.Parameters ip, IMethodData md, System.Boolean& unreachable) [0x00087] in /second/home/cvs/mcs/mcs/codegen.cs:796 csharp> * Important: we need to replace TypeBuidlers with Types after things have been emitted, or stuff like this happens: csharp> public class y {} csharp> typeof (y); Class1 * Clearing data TODO: when clearing data for variables that have been overwritten we need to check for structs and clear all the fields that contain reference types. * DEBATABLE: Implement auto-insert-semicolon This is easy to implement, just retry the parse with a semicolon, the question is whether this is a good idea to do in the first place or not.