17 lines
848 B
Markdown
17 lines
848 B
Markdown
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# Compatibility layer
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This directory provides an additional compatibility layer between ES modules and CommonJS.
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## Why?
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Both `./cjs/compat.ts` and `./esm/compat.ts` are written as ES modules, but `./cjs/compat.ts` can additionally use NodeJS CommonJS globals such as `__dirname` and `require` while these are disabled in ES module mode. For more information, see [Differences between ES modules and CommonJS](https://nodejs.org/api/esm.html#differences-between-es-modules-and-commonjs).
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## Adding exports
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In order to add exports, two things need to be done:
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- The exports must be declared in `src/compat.ts`.
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- The exports must be realized in `./cjs/compat.ts` and `./esm/compat.ts`.
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In the event `compat.ts` becomes too large, you can place declarations in another file. Just make sure `./cjs`, `./esm`, and `src` have the same structure.
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