[Haskell-cafe] Bikeshedding request for GHCi's :type

Takenobu Tani takenobu.hs at gmail.com
Tue May 3 15:14:33 UTC 2016

Hi Richard,

I like your decision and plan.
Thank you a lot of work, for community.

About new command name for (1):

Most users, perhaps, have entered the `:t` rather than `:type`.

  ghci> :t  length

In the same way, how about a full name and abbreviation name for (1).
For example, we prepare `:type-default` and `:td`.

  ghci> :td  length

So they don't misunderstand that it is "typedef".

I also like `:type!` and `:types` with Jack :)

  ghci> :t!  length


2016-05-03 5:10 GMT+09:00 Richard Eisenberg <eir at cis.upenn.edu>:

> I have collected feedback gleaned here, on the ticket, and on reddit and
> summarized here:
> https://ghc.haskell.org/trac/ghc/wiki/Design/GHCi/Type#Summaryoffeedbackaboutthisissue
> That summary includes this concrete proposal:
>  1. Ask for concrete suggestions about names for the new commands.
>  2. Use these names on my current implementation (which prints out only
> one specialization)
>  3. Post a feature request looking for more specializations.
> I simply don't have time to specify a design or implement an algorithm for
> printing out multiple specializations. Furthermore, my current
> implementation meets all specifications proffered for printing out multiple
> specializations, for all values of "multiple" that equal 1. It is easy to
> extend later.
> Separately, there is a groundswell of support for :doc, but that's beyond
> the scope of my work on this point. (I personally would love :doc, too.)
> So, what shall we name the two new commands?
> 1. A new command that specializes a type. (Currently with one
> specialization, but perhaps more examples in the future.)
> 2. A new command that preserves specialized type variables so that users
> of TypeApplications know what type parameters to pass in next.
> I have suggested :type-def for (1) and :type-spec for (2). I don't
> strongly like either. :examples and :inst have been suggested for (1). Any
> other ideas?
> Thanks!
> Richard
> On Apr 26, 2016, at 9:08 AM, Richard Eisenberg <eir at cis.upenn.edu> wrote:
> > Hi devs,
> >
> > Over the weekend, I was pondering the Haskell course I will be teaching
> next year and shuddered at having to teach Foldable at the same time as
> `length`. So I implemented feature request #10963 (
> https://ghc.haskell.org/trac/ghc/ticket/10963), which allows for a way
> for a user to request a specialization of a type. It all works wonderfully,
> but there is a real user-facing design issue here around the default
> behavior of :type and whether or not to add new :type-y like commands. I
> have outlined the situation here:
> https://ghc.haskell.org/trac/ghc/wiki/Design/GHCi/Type
> >
> > I'd love some broad input on this issue. If you've got a stake in how
> this all works, please skim that wiki page and comment on #10963.
> >
> > Thanks!
> > Richard
> > _______________________________________________
> > ghc-devs mailing list
> > ghc-devs at haskell.org
> > http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/haskell-cafe/attachments/20160504/d1979187/attachment.html>

More information about the Haskell-Cafe mailing list