How to get synchronous readline, or “simulate” it using async, in nodejs?

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Just in case someone stumbles upon here in future

Node 11.7 added support for this using async await

const readline = require('readline');
//const fileStream = fs.createReadStream('input.txt');

const rl = readline.createInterface({
  input: process.stdin, //or fileStream 
  output: process.stdout
});

for await (const line of rl) {
  console.log(line)
}

Remember to wrap it in async function(){} otherwise you will get a reserved_keyword_error.

const start = async () =>{
    for await (const line of rl) {
        console.log(line)
    }
}
start()

To read an individual line, you can use the async iterator manually

const it = rl[Symbol.asyncIterator]();
const line1 = await it.next();

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