RosettaCodeData/Task/Classes/Haskell/classes-3.hs

22 lines
499 B
Haskell

class Example (x) # 'x' is a field in class
# method definition
method double ()
return 2 * x
end
# 'initially' block is called on instance construction
initially (x)
if /x # if x is null (not given), then set field to 0
then self.x := 0
else self.x := x
end
procedure main ()
x1 := Example () # new instance with default value of x
x2 := Example (2) # new instance with given value of x
write (x1.x)
write (x2.x)
write (x2.double ()) # call a method
end