Is it possible to use both CommonJS and ES6 module in a Node.JS command-line program?

0
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I'm working on a CLI tool. I used "commander", which is a CommonJS module, to parse command-line arguments. I also want to use "p-map" to manage concurrency. However, "p-map" is a ES6 module.

Also I'm using Typescript.

Now both code editor and Typescript compiler won't complain. However I cannot execute my CLI tool. If I compile with "module":"commonjs", node would not load p-map and complains "Must use import to load ES Module... node_modules/p-map/index.js...require() of ES modules is not supported.". If I compile with "module":"es2015", use "require" to import the CommonJS modules, and add "type":"module" in my package.json, node would complain "ReferenceError: require is not defined".

I love the flexibility of Typescript/Javascript, however, it's time like this makes me miss Java. Java might be too prissy, but I don't spend hours trying to figure out import / export......

So, is it possible to use both CommonJS and ES6 module in a Node.JS command-line program?

1
javascriptnode.jstypescriptecmascript-6module
Use ESM and import the cjs module. That should work. Alternatively, as the linked page states, you can use dynamic import for the other way, if really needed. – ASDFGerte
Thanks for responding! I tried ECM import the cjs module, yes it works. I didn't know that I could import cjs module, not just using "require()". I also tried dynamic import. It SHOULD work. However the problem is Typescript always compiles my dynamic import() into require(). – Bing Ren
Will you please put your response as an answer so I can accept it as the correct answer? Thanks again! – Bing Ren

1 Answers

1
votes

To enhance compatibility, the (moderately new) node esm loader can import cjs-modules (e.g. import identifier from 'cjs-module-name';).

The other way around doesn't work, you can't require an esm-module, but dynamic import should work, if really necessary.

A related read may be the statement from p-map's owner regarding the topic.