Ruby conversion functions pattern

conversion_functions.rb

# From Confident Ruby, page 72

module Graphics
    module Conversions
        module_function

        def Point(*args)
            case args.first
            when Point   then args.first
            when Array   then Point.new(*args.first)
            when Integer then Point.new(*args)
            when String  then Point.new(*args.first.split(':').map(&:to_i))
            else
                raise TypeError, "Cannot convert #{args.inspect} to Point"
            end
        end
    end

    Point = Struct.new(:x, :y) do
        def inspect
            "#{x}:#{y}"
        end
    end
end

Graphics::Conversions::Point(3, 5) # => 3:5

include Graphics
include Graphics::Conversions

Point(Point.new(2, 3)) # => 2:3
Point([9, 7])          # => 9:7
Point(3, 5)            # => 3:5
Point('8:10')          # => 8:10