[Haskell-cafe] Will changing associativity of enumerator's ($=) affect anyone? (also: enumerator mailing list)
ben at 0x539.de
Sat Oct 15 19:46:21 CEST 2011
As a recent newbie, I would like to confirm the parent's report. I
eventually managed to think of the parentheses, but it did leave me
stumped for a while on thursday.
On Sa, 2011-10-15 at 12:49 -0400, David McBride wrote:
> This would be a big boon to newbies. When I first started using the
> library I would get big errors using $= that were because I didn't
> have parenthesis I needed, but didn't realize I needed, despite the
> fact that the types seemed to line up.
> On Sat, Oct 15, 2011 at 12:40 PM, Michael Snoyman <michael at snoyman.com> wrote:
> > On Sat, Oct 15, 2011 at 4:59 PM, John Millikin <jmillikin at gmail.com> wrote:
> >> A user recently suggested changing the associativity of ($=) 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.
> > Michael
> > _______________________________________________
> > Haskell-Cafe mailing list
> > Haskell-Cafe at haskell.org
> > http://www.haskell.org/mailman/listinfo/haskell-cafe
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
More information about the Haskell-Cafe