font>`)
    }
    function cls() { out.innerHTML = '' }
    const backupFileName = '_backup.jside'

    function readFile(file) {
      let reader = new FileReader()
      reader.onload = function() {
        input.value = reader.result
      }

      reader.onerror = function() {
        err(reader.error)
      }

      reader.readAsText(file)
    }

      function run() {
        if (autosave) backup()
        cls()
        try {
          eval(input.value)
        } catch (e) {
          err(e.message)
 