un-used record wildcards

Antoine Latter aslatter at gmail.com
Wed Oct 13 14:47:11 EDT 2010

On Wed, Oct 13, 2010 at 1:02 PM, Serge D. Mechveliani <mechvel at botik.ru> wrote:
> Dear GHC developers,
> I use the language extension of RecordWildcards, for example,
>                                f (Foo {foo1 = n, foo2 = m, ..}) = ...
> But the complier warns about un-used values of  foo3, foo4,
> probably, due to the extension of
>                     Foo {foo1 = n, foo2 = m, foo3 = foo3, foo4 = foo4}.
> In such cases, these warnings look as unneeded.
> Is it possible to have an un-used binding warnings with exception for
> wildcards in records?
> If not, then has it sense to introduce an option?

If you're not using foo3 and foo4, can you not put it the ellipsis?
that won't cover every case (such as where you're using foo3 but not


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