Precedence: 7
`yio` - [Y]oneda [I]dentity c[O]variant
How to read: modify the second argument covariantly, ignore the first one.
Works the same way as yo but for a 2-nd argument of a functor.
`yo` : t a `AR_` into (from a o) (t o)
`yio` : t _ a `AR_` into (from a o) (t _ o)
`ho` : t _ a `AR_` into (from a o) (t _ o)
It works identically to ho, the only difference is a glyph appearance.