Webpack failing

[talesmgodois]

Hello I have a need to use webpack in my react native app.
I encountered a weird thing while building this.I dont think this is actually a bug because my react native project is working fine without build errors. But Its weird I`d like to understand how this happened, and if there is a possibility to make my webpack/babel build this file

What I think it's weird is that in the index.js file, there is a typescript notation. I wonder if the project is using another way to define and use types that is not typescript(If so, I probably need to add a new loader to my webpack config)