bitnum is a number between 0 and 31.
bit.set (bit.set (0, 3), 4) // bits 3 and 4 are on » 24
bit.set (0, 30) // only bit number 30 is on » 1073741824
string.hex (bit.set (0, 30)) // hex format is useful for viewing bit patterns » "0x40000000"
bit.clear
string.hex