jeremyckahn · February 14, 2017 20:48
diff --git a/delete-random-lines.js b/delete-random-lines.js
 // Usage:
 // node delete-random-lines.js some-file.txt

 require('fs').readFile(process.argv[2], 'utf-8', (err, file) => {
  const lines = file.split('\n');
  const linesToDelete = Math.round(lines.length * 0.1);

  for (let i = 0; i < linesToDelete; i++)
    lines.splice(
      Math.floor(Math.random() * lines.length),
      1
    );

  console.log(lines.join('\n'));
 });