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@rauschma
Last active April 8, 2018 02:25
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Polyfillying the standard library when using babel-preset-env

Browsers

Approach for untranspiled code (meant to be transpiled by Babel and, e.g., webpack):

  • No package ever polyfills.
    • Use only functionality at stage 4 or older.
  • The entry point does import "babel-polyfill"; for which env.useBuiltins generates the imports appropriate for the current targets.
    • Benefit: the bundle only includes functionality that the target platforms don’t have. Think: custom-tailored babel-polyfill.

Node.js

For Node.js, the untranspiled code would be transpiled via target: { node: "current" }.

  • To play it safe, should every package do import "babel-polyfill"; at its entry point?
    • Note: not as problematic, because bundle size is not a factor on Node.js.
@prichodko
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First of all, thanks for this gist!
I have two question, I'd like to clarify. Does babel-polyfill include regeneratorRuntime? And how to deal with a situation, when a library has to support browser and node.js?

@rauschma
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