Strong +1 from me, this is *especially* annoying when you want to selectively re-export parts of a module from somewhere or in case of exports generated by TH. Cheers, Merijn

On 26 Oct 2014, at 12:28, Tom Murphy wrote:

(Not to be confused with the "hiding import behavior" discussion also going on)

--

Currently, I'm able to write "module Foo where" to export everything defined in Foo.

If, though, I add to the module some definitions which I don't want to export...

data Lockbox = MkLockbox Int

internalFunction = ...

...I then have to explicitly enumerate everything that I *do* want the module to export, and add to that list each time I add to the module.

I propose that instead, we're able to simply say what we mean:

module Foo hiding (Lockbox(MkLockbox), internalFunction) where

I think its semantics are immediately clear to the reader.

There's a little bit of bikeshedding that needs to happen (e.g. is "hiding (Foo(..))" sufficient to hide the type Foo and not just its constructors), but are people +1 on this? I've frequently wanted this behavior.

Tom

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On 2014-10-26 at 20:28:41 +0100, Tom Murphy wrote: [...]

I propose that instead, we're able to simply say what we mean:

module Foo hiding (Lockbox(MkLockbox), internalFunction) where

I think its semantics are immediately clear to the reader.

There's a little bit of bikeshedding that needs to happen (e.g. is "hiding (Foo(..))" sufficient to hide the type Foo and not just its constructors), but are people +1 on this? I've frequently wanted this behavior.

I'm generally +1 on this, and I even suggested that one myself some time ago: http://www.haskell.org/pipermail/haskell-prime/2014-January/003910.html Cheers, hvr

On 2014-10-26 at 20:28:41 +0100, Tom Murphy wrote: [...]

module Foo hiding (Lockbox(MkLockbox), internalFunction) where

I think its semantics are immediately clear to the reader.

There's a little bit of bikeshedding that needs to happen (e.g. is "hiding (Foo(..))" sufficient to hide the type Foo and not just its constructors), but are people +1 on this? I've frequently wanted this behavior.

PS: As for semantics, I'd suggest to have module Foo hiding (Lockbox(MkLockbox), internalFunction) where the same effect moving the definitions of `Foo` into an hidden/internal module `_Foo` and having `Foo` re-export it in the following way: module Foo (module _Foo) where import _Foo hiding (Lockbox(MkLockbox), internalFunction) that should result the least surprise IMHO Cheers, hvr

Hi Tom, +1

There's a little bit of bikeshedding that needs to happen (e.g. is "hiding (Foo (..))" sufficient to hide the type Foo and not just its constructors), but are people +1 on this? I've frequently wanted this behavior.

I would be surprised if 'Foo(..)' would mean in this case something different, so yes, the type Foo should be hidden too. Greetings, Daniel