Using function:
functor
import
Application
System
define
fun {Add X}
fun {$ N} X+N end
end
{System.showInfo {{Add 10} 20}}
{Application.exit 0}
end
Using procedure:
functor
import
Application
System
define
proc {Add X P}
P = proc {$ N R} R = N+X end
end
{System.showInfo {{Add 10} 20}}
{Application.exit 0}
end