Decimal is a struct that wraps NSDecimalNumber so you can use it like other types (Float, Int, Double, Int64, etc)

testNSDecimalNumberWrapper.swift

    func testSomeStuff() {
        // trying to come up with shit to test.
        
        var d: Decimal = 1234
        
        print(d)
        
        d += 2
        
        print(d)
        
        d++
        
        print(d)
        
        var b = ++d
        
        print(b, d)
        
        b *= 3.14
        
        print(b)
        
        b /= 2
        
        print(b)
        
        
        // make sure the behavior is the same as the normal int/float types.
        let neg = Decimal(-200.4)
        let fneg = -200.4
        
        print(+neg, +fneg)
        print(-neg, -fneg)
        
        let pos = Decimal(200.4)
        let fpos = 200.4
        
        print(-pos, -fpos)
        print(+pos, +fpos)
    }

test increments of .1