Every package in this monorepo should have an index.ts file in the src/ directory. Any symbols that this file exports will be usable by consumers.
It is tempting to save time by re-exporting all symbols from one or many files by using the "wildcard" or "barrel" export syntax:
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export * from './foo-controller';
export * from './foo-service';However, using this syntax is not advised for the following reasons:
- Barrel exports make it difficult to understand the public surface area of a package at a glance. This is nice for general development, but is especially important for debugging when sorting through previously published versions of the package on a site such as
npmfs.com. - Any time a new export is added to one of these files, it will automatically become an export of the package. That may sound like a benefit, but this makes it very easy to increase the surface area of the package without knowing it.
- Sometimes it is useful to export a symbol from a file for testing purposes but not expose it publicly to consumers. With barrel exports, however, this is impossible.
Instead of using barrel exports, name every export explicitly:
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export { FooController } from './foo-controller';
export type { FooControllerMessenger } from './foo-controller';
export { FooService } from './foo-service';
export { FooService } from './foo-service';
export type { AbstractFooService } from './foo-service';