Implement AST reflection

[krame505]

This implements the reflectAST operation as described in #212. Next up is reify.

[krame505]

@tedinski @ericvanwyk Anything that I should fix before merging this?

[tedinski]

Text from copy and paste?

[krame505]

Oops...

[tedinski]

General thoughts:

1. Not sure if we should have AST have a pp, but for now okay no problem. But I think we could probably avoid the dependency on langutil in the final version?
2. In the end, we probably need tests that do better than compare to string (too brittle?), but obviously I think that's hard to do yet? So ok.

Probably good to merge.

[ericvanwyk]

Ok with me.

…

On Thu, Jan 11, 2018 at 3:45 PM, Ted Kaminski ***@***.***> wrote: General thoughts: 1. Not sure if we should have AST have a pp, but for now okay no problem. But I think we could probably avoid the dependency on langutil in the final version? 2. In the end, we probably need tests that do better than compare to string (too brittle?), but obviously I think that's hard to do yet? So ok. Probably good to merge. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#213 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ADOhd9z8ScxIzeip8BYPQW-4nY2CMPz1ks5tJoD2gaJpZM4RTxKM> .

[krame505]

1. Not sure if we should have AST have a pp, but for now okay no problem. But I think we could probably avoid the dependency on langutil in the final version?

Yeah, I suppose those equations could move to aspects in the langutil library.

2. In the end, we probably need tests that do better than compare to string (too brittle?), but obviously I think that's hard to do yet? So ok.

Agreed, we really need a derivable equality typeclass for this...
I'll go ahead and merge.