Duplicate export for enums error

Hi, I have the following format for enums in my code:

```
export enum UserRolesEnum {
ADMIN,
OTHER
}
```

```
export namespace UserRolesEnum {
export function toString(v: UserRolesEnum): string {
return UserRolesEnum[v];
}

export function stringToEnum(input: string): UserRolesEnum {
let enumString: UserRolesEnum = UserRolesEnum[input];
return enumString;
}
}
```

> I'm getting the following error:
> Error: Duplicate export 'UserRolesEnum'
> at error (...node_modules/gulp-rollup/node_modules/rollup/dist/rollup.js:185:14)
> at Module.error (...node_modules/gulp-rollup/node_modules/rollup/dist/rollup.js:8170:3)
> at tryParse (...node_modules/gulp-rollup/node_modules/rollup/dist/rollup.js:7888:10)
> at new Module (...node_modules/gulp-rollup/node_modules/rollup/dist/rollup.js:7924:15)
> at load.catch.then.then.then.source (...node_modules/gulp-rollup/node_modules/rollup/dist/rollup.js:9749:20)
> at process._tickCallback (internal/process/next_tick.js:109:7)

Is there a way to fix this without renaming my enums and namespaces?

Start by reproducing the reported TypeScript enum and namespace export with the generator's gulp-rollup setup, then trace the Rollup duplicate-export error in the build configuration. Done means the example builds without renaming UserRolesEnum or its namespace; the payload names no repository files or tests to run.

Written by the indexing model from the issue text.