Normal Distribution lib in Swift

Calculate a standard normal distribution:

let x = 0.0
let dist = ø(x)

Calculate a general normal distribution:

let x = 0.0
let dist = normalDistribution(0.0, 1.0)(x)

Use a general normal distribution as a variable:

let x = 0.0
let f = normalDistribution(0.0, 1.0)
let dist = f(x)