How to get command line input?

1

I just tried to write a very simple cli program using rescript and node.

How to read command line input like scanf/cin in cpp?

2

Ja can follow this tutorial Using stdout, stdin, and stderr in Node.js - LogRocket Blog

Probably you have to create bindings for the functions you will use. Here are some threads and the documentation can help you to write these.

3

There are already bindings for this rescript-nodejs/Process.res at 66a558001767c9dfd4d2a2fd6c7e56fd1530d60a · TheSpyder/rescript-nodejs · GitHub

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4

I know this was over a year ago but in trying to find a solution for ReScript Bun this question is the only thing in the forum so thought I’d post a solution I cobbled together after a lot of googling. I’m using rescript-bun but I guess a similar solution should work for rescript-nodejs.

let {close, question} = module(Readline.Interface)
let rl = Readline.make({
  input: %raw(`process.stdin`),
  output: %raw(`process.stdout`),
})

let answer = await Promise.make((resolve, _reject) => {
  rl->question("? ", resolve)
})

answer->Console.log
rl->close

I was struggling to find what was a RescriptBun.Stream.Readable.subtype<RescriptBun.Buffer.t, 'rtype> for the input and output fields, so I found a similar solution in an old ReasonML forum that used the %raw solution to provide process.stdin/stdout.

I found out via stackoverflow how to get the command line input value out by wrapping the question call in a promise.

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