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[Question] Sub-exports depending on main export bundle the entire main-export.

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#1,027 3 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
javascript, rollup, typescript
Domain
build-system, tooling

Research direction

Start with the index.ts, main.ts, and a.ts examples and inspect how microbundle produces the dist/a.* outputs for each format. Check the package.json sub-export configuration and Rollup external handling first. Done means the ./a bundles avoid inlining main.ts while preserving the requested import and UMD usage.

Written by the indexing model from the issue text.

Description

I have a project where I have a main-export and multiple other exports. The other exports are extensions that depend on the main-export, but I don't want them to be in the main-export to keep it as small as possible.

Users should be able to do:

import {Thing} from 'package';

// optional addition
import {OtherThing} from 'package/a';

(or similarly using multiple script-tags with the umd-builds)

As for the source-files, it's roughly like this:

// index.ts
export * from './main';

// main.ts
export class Thing {}

// a.ts
import {Thing} from './main';

export class OtherThing extends Thing {}

And the package.json contains these sub-exports:

"exports": {
    ".": {
      "import": "./dist/index.modern.js",
      "require": "./dist/index.js",
      "umd": "./dist/index.umd.js",
      "browser": "./dist/index.module.js"
    },
    "./a": {
      "import": "./dist/a.modern.js",
      "require": "./dist/a.js",
      "umd": "./dist/a.umd.js",
      "browser": "./dist/a.module.js"
    },
  }

With this, the output-files for './a' (all formats) have the entire definition of './main.ts' inlined.

So my question is, is there a way to configure microbundle to treat those other files as externals?

Dominant language
JavaScript
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Forks
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