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Kingwl · Kingwl · commit 22672f33877b · 2018-09-07T11:45:32.000+08:00
diff --git a/src/compiler/visitor.ts b/src/compiler/visitor.ts
@@ -268,6 +268,7 @@ namespace ts {
                     nodesVisitor((<PropertyDeclaration>node).decorators, visitor, isDecorator),
                     nodesVisitor((<PropertyDeclaration>node).modifiers, visitor, isModifier),
                     visitNode((<PropertyDeclaration>node).name, visitor, isPropertyName),
+                    // QuestionToken and ExclamationToken is uniqued in Property Declaration and the signature of 'updateProperty' is that too
                     (visitNode((<PropertyDeclaration>node).questionToken, tokenVisitor, isToken), visitNode((<PropertyDeclaration>node).exclamationToken, tokenVisitor, isToken)),
                     visitNode((<PropertyDeclaration>node).type, visitor, isTypeNode),
                     visitNode((<PropertyDeclaration>node).initializer, visitor, isExpression));
