Generate code that throws an exception on unimplemented features.

dart/frog/leg/typechecker.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class TypeCheckerTask extends CompilerTask {
   TypeCheckerTask(Compiler compiler) : super(compiler);
   String get name() => "Type checker";
 
   static final bool LOG_FAILURES = false;
 
@@ skipping 615 matching lines @@
 
   visitEmptyStatement(EmptyStatement node) {
     return StatementType.NOT_RETURNING;
   }
 
   visitBreakStatement(BreakStatement node) {
     return StatementType.NOT_RETURNING;
   }
 
   visitContinueStatement(ContinueStatement node) {
-    compiler.unimplemented('visitContinueStatement', node: node);
+    return StatementType.NOT_RETURNING;
   }
 
   visitForInStatement(ForInStatement node) {
     analyze(node.expression);
     StatementType bodyType = analyze(node.body);
     return bodyType.join(StatementType.NOT_RETURNING);
   }
 
   visitLabelledStatement(LabelledStatement node) {
     return node.statement.accept(this);
   }
 
   visitLiteralMap(LiteralMap node) {
-    compiler.unimplemented('visitLiteralMap', node: node);
+    fail(node);
   }
 
   visitLiteralMapEntry(LiteralMapEntry node) {
-    compiler.unimplemented('visitLiteralMapEntry', node: node);
+    fail(node);
   }
 
   visitNamedArgument(NamedArgument node) {
     fail(node, 'named argument not implemented');
   }
 
   visitSwitchStatement(SwitchStatement node) {
-    compiler.unimplemented('visitSwitchStatement', node: node);
+    fail(node);
   }
 
   visitTryStatement(TryStatement node) {
     fail(node, 'unimplemented');
   }
 
   visitScriptTag(ScriptTag node) {
-    compiler.unimplemented('visitScriptTag', node: node);
+    fail(node);
   }
 
   visitCatchBlock(CatchBlock node) {
-    compiler.unimplemented('visitCatchBlock', node: node);
+    fail(node);
   }
 
   visitTypedef(Typedef node) {
-    compiler.unimplemented('visitTypedef', node: node);
+    fail(node);
   }
 }