svelte-ie-webpack-example

Webpack config example of polyfill and transpile needed for svelte to support IE 11

polyfill:

1. core-js
2. regenerator-runtime
3. custom element polyfill, for example: @webcomponents/custom-elements

transpile

1. setup babel and babel-loader (webpack)
2. setup babel-loader to exclude node_module but include svelte
   1. if you're using windows, the regex of path needed to be windows-style(\).
   2. The test property of babel-loader must be changed to include .mjs (/\.m?js$/) because svelte's runtime use .mjs extension.
   3. don't transpile core-js. if you transpile it, polyfill won't work.
3. setup babel-loader to transpile svelte file. Noted in the use property svelte-loader must be after babel-loader, so that svelte-loader would execute first.