## Stream: new members

### Topic: Documentation on superclasses

#### Jannis Limperg (Apr 02 2020 at 16:57):

Hey! Is there any documentation on how exactly Lean's typeclass hierarchies (e.g. the extends keyword) work? I've looked at the reference manual and TPIL, but have come up empty.

#### Jannis Limperg (Apr 02 2020 at 17:14):

Ah, extends is documented under 'Structures', so never mind that. I'm still not exactly sure how things work, but maybe that'll get me to a point where I have more specific questions.

Last updated: May 14 2021 at 04:22 UTC