unit LedN em.hal/LedN.em 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23package em.hal import LedI module LedN: LedI # ^| Nil implementation of the LedI interface end def isOn() return false end def on() end def off() end def toggle() end def wink(usecs) end