How to resolve React: Module parse failed: Identifier directly after number (numberic separator) #233

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For those that may get a build error similar to the following when using color in a React (CRA/react-scripts) project:

./node_modules/color/index.js 246:28
Module parse failed: Identifier directly after number (246:28)
File was processed with these loaders:
 * ./node_modules/react-scripts/node_modules/babel-loader/lib/index.js
You may need an additional loader to handle the result of these loaders.
|     for (const [i, element] of rgb.entries()) {
|       const chan = element / 255;
>       lum[i] = chan <= 0.039_28 ? chan / 12.92 : ((chan + 0.055) / 1.055) ** 2.4;
|     }
|

The following worked for me:

1. Make sure react-scripts is up to date.
2. Make sure that your browserslist definition include browsers that needs the transpilation (I believe the default does).
3. Update browserslist definitions: npx browserslist@latest --update-db
4. Delete any babel cache: rm -r node_modules/.cache/

My basic understanding is that react-scripts includes babel-env which includes the babel-plugin-proposal-numeric-separator, but it doesn't think it needs to transpile that specific issue and just needs a little help.

@Qix- Thanks for the great module. Though this issue is not really specific to this package, your un-empathetic response to this issue is unfortunate. Some docs on what browsers/environments you aim to support with your package would be appreciated.