webpack and TypeScript 2.0: Duplicate identifier

Question

I'm currently using TypeScript 2.0 (and webpack 1.13.2) along with the "@types" definition and I'm currently have the following error:

ERROR in [default] ###\node_modules\@types\js-base64\index.d.ts:53:4 Duplicate identifier 'export='.

I'm showing this error but it's not actually the only one I have. Indeed, recently, I added "ckeditor" to my project and downloaded the corresponding typings via

npm install @types/ckeditor --save-dev

My code compiles correctly, but now I have dozens of errors of type "Duplicate identifier". The weird thing is that I exclude "node_modules" via my "tsconfig.json":

{
  "compilerOptions": {
    "target": "es5",
    "module": "commonjs",
    "moduleResolution": "node",
    "sourceMap": true,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "removeComments": false,
    "noImplicitAny": true,
    "suppressImplicitAnyIndexErrors": true
  },
  "exclude": [
    "node_modules"
  ]
}

So I don't get how come it creates warning/error.

Btw, I tried with webpack 2 and it does not solve the issue.

Matt Martin Matt Martin · Accepted Answer · 2016-10-23T01:13:15

If you didn't find the issue yet, it's likely the result of having two definition files present in your project.

I ran into this, for example, when migrating from typings to @types via npm — I had a definition in both locations.

webpack and TypeScript 2.0: Duplicate identifier

1 Answers