[pie_flavor]

On the "clunky syntax" doc comment: a thing typenum does repeatedly is to define generic typedefs that become trait exprs. For example,

  type If<Cond, Then, Else> = <(Then, Else) as If<Cond>>::Output;

[doctor_n_]

I was unaware of typenum until I started showing people this - I'm actually amazed at the level of effort that's gone into it.