1d.fs

[<Measure>] type Length
[<Measure>] type Area = Length*Length
let area (a : float<Length>) (b: float<Length>) = 2.0*a*b
let a1:float<Area> = area 0.0<Length> 1.0<Length>
let a2:float<Area> = area 1.0<Length> 0.0<Length>
let a3:float<Area> = area 1.0<Length> 1.0<Length>
("for 0,1: " + a1.ToString()).Dump()
("for 1,0: " + a2.ToString()).Dump()
("for 1,1, circle should be pi: " + a3.ToString()).Dump()

for 0,1: 0
for 1,0: 0
for 1,1, circle should be pi: 2