Proposal: Add cons function to Data.List module

Taylor Fausak taylor at
Wed Sep 11 11:20:59 UTC 2019

I suspect this proposal was not made in good faith. I feel like it was meant to make fun of my list singleton proposal. 

In spite of that, I am in favor of this proposal. One of the (very minor!) problems with lists in Haskell is that they can’t be documented with Haddock because they’re part of the syntax. For example, if you search Hoogle for `(:)` or `a -> [a] -> [a]` you won’t find the venerable list constructor. You will find `cons` from the `extra` package, which I think suggests that this proposal is a good idea.


> On Sep 11, 2019, at 4:13 AM, Oliver Charles <ollie at> wrote:
> On Wed, Sep 11, 2019 at 7:36 AM Helmut Schmidt
> < at> wrote:
>> I can't be the only that wants this function, right?
> You're not the only one! I would also like this function. In fact,
> only yesterday I found myself writing
>  ( x : ) <$> recurse xs
> I would have preferred
>  cons x <$> recurse xs
> +1 to adding  cons :: x -> [x] -> [x]  to  Data.List.
> Ollie
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