Fix function type error in README

[ahuglajbclajep]

Fix type error of greet function in README.
See also #1.

Also, TypeScript does not allow the addition of ".ts" when importing *.ts.
https://www.typescriptlang.org/docs/handbook/modules.html#import
I also fix the README small mistake about this behavior.

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[ahuglajbclajep]

@googlebot I signed it!

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[ahuglajbclajep]

@developit I’d love your feedback, please review my PR.

[gfoidl]

Maybe in the webpack.config.js there should also be a comment about additional loaders for typescript, like ts-loader?

So the config looks like:

module.exports = {
  module: {
    rules: [
      {
        test: /\.worker\.(js|ts)$/i,
        use: [{
          loader: 'comlink-loader',
          options: {
            singleton: true
          }
        },
        "ts-loader"]
      }
    ]
  }
}

Otherwise there will / may be build-failures like

 Module parse failed: Unexpected token (2:25)
    File was processed with these loaders:
     * ../../node_modules/comlink-loader/dist/comlink-worker-loader.js
    You may need an additional loader to handle the result of these loaders.
    | import { expose } from 'comlink';
    ...

[ahuglajbclajep]

@gfoidl The README is correct in this regard, as it works if you write the comlink-loader first, as shown below.

module.exports = {
  module: {
    rules: [
      {
        test: /\.worker\.[tj]s$/,
        loader: "comlink-loader?singleton",
      },
      {
        test: /\.[tj]sx?$/,
        loader: "ts-loader",
        exclude: /node_modules/,
      }
    ]
  }
}

[gfoidl]

Ahhh, that's good to know. Thank you very much! 👍 😃