[Haskell-cafe] Will changing associativity of enumerator's ($=) affect anyone? (also: enumerator mailing list)

Michael Snoyman michael at snoyman.com
Sat Oct 15 18:40:50 CEST 2011

On Sat, Oct 15, 2011 at 4:59 PM, John Millikin <jmillikin at gmail.com> wrote:
> A user recently suggested changing the associativity of ($=) from [[
> infixr 0 ]] to [[ infixl 1 ]]. This allows the following expressions
> to be equivalent:
>   run $ enumerator $$ enumeratee =$ enumeratee =$ iteratee
>   run $ enumerator $= enumeratee $$ enumeratee =$ iteratee
>   run $ enumerator $= enumeratee $= enumeratee $$ iteratee
> Although this is technically a backward-incompatible change, I feel
> it's small enough that it could go in a minor release *if nobody
> depends on the current behavior*.
> So, if anybody using 'enumerator' will have code broken by this
> change, please speak up. If I don't hear anything in a week or so,
> I'll assume it's all clear and will cut the new release.
> -------------------------
> Second, I was asked whether there's a mailing list for enumerator
> stuff. To my knowledge there isn't, so I started one on librelist. To
> subscribe and/or post, send an email to
> haskell.enumerator at librelist.com . Archives are available at
> http://librelist.com/browser/haskell.enumerator/ . I plan to make
> release announcements there (for releases not important enough for
> haskell-cafe), and it might be useful for general discussion.

I'm strongly in favor of this change, the current associativity has
caused me to litter some code with a few too many parentheses.


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