Why tslib?

[janosh]

Still learning TypeScript so this may be a dumb question. setupTypeScript.js installs tslib:

template/scripts/setupTypeScript.js

Line 29 in f92a0a4

"tslib": "^2.0.0",

Reading the docs,

If the importHelpers flag is on, these helper functions are instead imported from the tslib module. You will need to ensure that the tslib module is able to be imported at runtime. This only affects modules; global script files will not attempt to import modules.

it sounds like there's no point in installing tslib unless you also set importHelpers to true in tsconfig.json which @tsconfig/svelte doesn't appear to do.

{
  "$schema": "https://json.schemastore.org/tsconfig",
  "display": "Svelte",
  "_version": "2.0.0",

  "compilerOptions": {
    "moduleResolution": "node",
    "target": "es2017",
    "importsNotUsedAsValues": "error",
    "isolatedModules": true,
    "sourceMap": true,

    "strict": false,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true
  }
}

I assume I'm missing something?