Hands-On Design Patterns and Best Practices with Julia

Example 1 – the ColorTypes.jl package

ColorTypes.jl is a package that defines various data types that represent colors. In practice, there are many ways in which a color can be defined: Red-Green-Blue (RGB), Hue-Saturation-Value (HSV), and so on. Most of the time, a color can be defined using three real numbers. In the case of grayscale, only a single number is required to represent the level of darkness. To support transparent colors, an additional value can be used to store an opacity value. First, let's take a look at the type definitions:

"""
`Colorant{T,N}` is the abstract super-type of all types in ColorTypes,
and refers to both (opaque) colors and colors-with-transparency (alpha
channel) information. `T` is the element type (extractable ...