github.com/l3x/learn-fp-go@v0.0.0-20171228022418-7639825d0b71/4-purely-functional/ch09-functor-monoid (about) 01_clock_functor 01_no_generics_nums 02_generics_cars 03_generics_nums 04_generics_nums 05_int_functor 06_compose 07_compose_gof 08_compose_fog 09_clock_functor 10_car_functor 11_monoid