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src/compiler/checker.ts

@@ -10982,6 +10982,8 @@ module ts {
         function getExportNameSubstitution(symbol: Symbol, location: Node): string {
             if (isExternalModuleSymbol(symbol.parent)) {
                 var symbolName = unescapeIdentifier(symbol.name);
+                // If this is es6 or higher, just use the name of the export
+                // no need to qualify it.
                 if (languageVersion >= ScriptTarget.ES6) {
                     return symbolName;
                 }

src/compiler/emitter.ts

@@ -4903,6 +4903,7 @@ module ts {
                 }
 
                 write("class ");
+                // check if this is an "export default class" as it may not have a name
                 if (node.name || !(node.flags & NodeFlags.Default)) {
                     emitDeclarationName(node);
                 }