Convert PostgreSQL's WAL_LSN to bytes (int, possibly 64-bit width?)

wal_lsn_to_int.js

/**
 * Logic is from:
 *   https://stackoverflow.com/questions/66797767/lsn-external-representation
 * You may also look at:
 *   https://www.crunchydata.com/blog/postgres-wal-files-and-sequuence-numbers
 */

function lsn2int (str) {
  return parseInt(
    str.split('/').map((n) => n.padStart(8, '0')).join(''),
    16
  );
};

console.log(lsn2int('16/374D848'));
// => 94547269704