The callback to execute when the Promise is settled (fulfilled or rejected).
A Promise for the completion of the callback.
Attaches callbacks for the resolution and/or rejection of the Promise.
The callback to execute when the Promise is resolved.
The callback to execute when the Promise is rejected.
A Promise for the completion of which ever callback is executed.
Attaches a callback that is invoked when the Promise is settled (fulfilled or rejected). The resolved value cannot be modified from the callback.