How to access the contents of the closure from the outside

Question

I use the following code to read the file line by line. But the content of the line is in a closure, what can I do to access the contents of the line outside?The module I am using is the internal module of node.js

  var fs=require("fs")
 function readFirstLine(){
    var firstfile = [];
    readline = require('readline');

    var rd = readline.createInterface({
        input: fs.createReadStream('somefile.txt'),
        output: process.stdout,
        terminal: false
    });

    rd.on('line', function(line) {
        console.log(line)  
    }
    );

}
    readFirstLine()

You can't and you shouldn't. This is the same problem as https://stackoverflow.com/questions/14220321/how-do-i-return-the-response-from-an-asynchronous-call — Estus Flask, Mar 11 '19 at 12:28

score 0 · Accepted Answer · answered Mar 11 '19 at 12:37

0

You can push each line to external array, but you won't know when the readline finish to read the file.

The easiest way, with async/await.

How do I return the response from an asynchronous call?

answered Mar 11 '19 at 12:37

yeya

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How to access the contents of the closure from the outside

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