Alex Knauth

It's not that it doesn't work properly, it's that it's annoying to have to recompile it when it seems like a package info.rkt for a multi-collect pkg doesn' need a...

A `(lens-join/list X-piece-lens ...)` lens only follows the lens laws when this is true for all `X`. ```racket (lens-set* X {~seq X-piece-lens (lens-view X-piece-lens X)} ...) = X ``` (Edit:...

But that's not the only condition. It also needs these properties for all sets of `X-piece ...`: ```racket (lens-view X-piece-lens (lens-set* X {~seq X-piece-lens X-piece} ...)) = X-piece ... ```

See https://github.com/jackfirth/lens/pull/179#issuecomment-134367592

In addition to that, rekey could even be made into a lens like this: (Edited) ``` racket > (define (rekey-lens key->new-key-lens) (lens-zoom hash->set-lens (set-mapper-lens (lens-zoom car-lens key->new-key-lens)))) ``` This would...

Do you mean add new features in `lens/private/` but don't reprovide them from `lens/main.rkt` and have `unstable/lens.rkt` reprovide them instead? Yeah, that sounds like a much better idea.

I believe this issue should be transferred to the `htdp` repository: https://github.com/racket/htdp

This seems like a cop-out, and it is, but I didn't try to put a proper explanation of isomorphisms in there because I had no idea what an isomorphism was...

Calling it `stx-improper-lens` would be wrong. The word "improper" should not be separated from the word "list." The words "improper syntax" could mean a lot of things other than an...

Names in `a->b` format can still make sense for lenses that aren't isomorphisms; think of `stx->list-lens`.