Monoid wants a (++) equivalent
|
View:
New views
20 Messages
—
Rating Filter:
Alert me
|
| < Prev | 1 - 2 - 3 - 4 | Next > |
 |
Re: Monoid wants a (++) equivalent
by ajb-2
::
Rate this Message:
G'day all.
Quoting John Meacham <john@...>: > (+>) seems to imply to me that the operator is non-associative. Something > like (<>) or (<+>) would be better. I tend to agree. Moreover, and I realise this may be a losing battle, I want (++) to be the generic operator. I understand the argument. I even agreed with it at the time. In 1998, academic use of Haskell (both for research and education) was the most important imperative. Today, Haskell is officially cool, so the good names and operators should not be stolen by operations that are distinguished only by being less useful (e.g. by working on lists alone). Cheers, Andrew Bromage _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by ajb-2
::
Rate this Message:
G'day all.
On Tue, Jun 30, 2009 at 08:02:48PM -0400, Daniel Peebles wrote: > But we don't want to imply it's commutative either. Having something > "bidirectional" like <> or <+> feels more commutative than associative > to me. Quoting John Meacham <john@...>: > Not really, think of '++', which doesn't commute but is visually > symmetric, or Data.Sequence.<>, or the common use of <> to mean > concatination in pretty printers. Other good examples are && and ||. Cheers, Andrew Bromage _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Ketil Malde-5
::
Rate this Message:
You know, this might be the right time to start expanding our vocabulary beyond seven bits. Since we're likely to keep mappend around as an alias for some time, people would have a grace period to adjust. How about U+2295 (circle with plus inside it)? Or, if we would like to stick to the 8-bit subset to keep those 8859-1 users happy, how about ¤ (funny circle over an x, U+00A4) -k -- If I haven't seen further, it is by standing in the footprints of giants _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Alex Dunlap
::
Rate this Message:
On Tue, Jun 30, 2009 at 11:24 PM, Ketil Malde<ketil@...> wrote:
> > You know, this might be the right time to start expanding our > vocabulary beyond seven bits. Since we're likely to keep mappend > around as an alias for some time, people would have a grace period to > adjust. > > How about U+2295 (circle with plus inside it)? > > Or, if we would like to stick to the 8-bit subset to keep those 8859-1 > users happy, how about ¤ (funny circle over an x, U+00A4) > > -k > -- > If I haven't seen further, it is by standing in the footprints of giants > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@... > http://www.haskell.org/mailman/listinfo/haskell-cafe > The major disadvantage of that is that those symbols are not on my keyboard and thus are more of a pain to type, especially on the Linux console where compose key is not available... Alex _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Jochem Berndsen-3
::
Rate this Message:
ajb@... wrote:
> G'day all. > > Quoting John Meacham <john@...>: > >> (+>) seems to imply to me that the operator is non-associative. Something >> like (<>) or (<+>) would be better. > > I tend to agree. Moreover, and I realise this may be a losing battle, > I want (++) to be the generic operator. I totally agree. (+>) is too asymmetric for my taste, like (>>=) and (*>) it suggests asymmetry between the arguments. (++) is symmetric and suggests an associative operator to me. -- Jochem Berndsen | jochem@... GPG: 0xE6FABFAB _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by david48
::
Rate this Message:
On Wed, Jul 1, 2009 at 9:34 AM, Jochem Berndsen<jochem@...> wrote:
> ajb@... wrote: >> I tend to agree. Moreover, and I realise this may be a losing battle, >> I want (++) to be the generic operator. > I totally agree. So do I. David. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Duncan Coutts
::
Rate this Message:
On Tue, 2009-06-30 at 18:31 -0700, John Meacham wrote:
> On Tue, Jun 30, 2009 at 08:02:48PM -0400, Daniel Peebles wrote: > > But we don't want to imply it's commutative either. Having something > > "bidirectional" like <> or <+> feels more commutative than associative > > to me. Of course in Text.PrettyPrint, both <> and <+> are associative but not commutative (with identity empty). > Not really, think of '++', which doesn't commute but is visually > symmetric, or Data.Sequence.<>, or the common use of <> to mean > concatination in pretty printers. I think there is a fair amount of > precedence for using '<>' actually. As it appears when it is used, it > is also the natural mappend operator for the Monoid instance. I agree, if we can't use ++ then <> is the next best thing. As John says it's already a monoid operator for Data.Sequence and Text.PrettyPrint. Duncan _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Jules Bean
::
Rate this Message:
Duncan Coutts wrote:
> I agree, if we can't use ++ then <> is the next best thing. As John says > it's already a monoid operator for Data.Sequence and Text.PrettyPrint. > I agree, if we can't use +> and <+ then <> is the next best thing. ;) Jules _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by david48
::
Rate this Message:
On Wed, Jul 1, 2009 at 2:18 PM, Jules Bean<jules@...> wrote:
> Duncan Coutts wrote: >> I agree, if we can't use ++ then <> is the next best thing. As John says >> it's already a monoid operator for Data.Sequence and Text.PrettyPrint. > I agree, if we can't use +> and <+ then <> is the next best thing. > ;) I see what you did there :-P _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Brent Yorgey-2
::
Rate this Message:
On Wed, Jul 01, 2009 at 12:00:50AM -0400, ajb@... wrote:
> G'day all. > > On Tue, Jun 30, 2009 at 08:02:48PM -0400, Daniel Peebles wrote: > >> But we don't want to imply it's commutative either. Having something >> "bidirectional" like <> or <+> feels more commutative than associative >> to me. > > Quoting John Meacham <john@...>: > >> Not really, think of '++', which doesn't commute but is visually >> symmetric, or Data.Sequence.<>, or the common use of <> to mean >> concatination in pretty printers. > > Other good examples are && and ||. ..wha? But those ARE commutative. Unless you mean with respect to strictness? -Brent _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by edwardk
::
Rate this Message:
I'm rather fond of the (<>) suggestion, but would be happy with anything better than mappend! ;)
-Ed
On Wed, Jul 1, 2009 at 8:56 AM, Brent Yorgey <byorgey@...> wrote:
_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Thomas Davie
::
Rate this Message:
On 1 Jul 2009, at 16:46, Edward Kmett wrote: > I'm rather fond of the (<>) suggestion, but would be happy with > anything better than mappend! ;) I find it rather ugly, it has a lot of connotations of "does not equals" from other languages. Personally I'm in favor of <+>, simply because it looks most like a circle with a plus in it. Bob _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Jason Dagit-2
::
Rate this Message:
On Wed, Jul 1, 2009 at 7:53 AM, Thomas Davie <tom.davie@...> wrote:
This is my favorite of the suggestions as well. Then again, I don't mind typing mappend. Yay for bikesheds :) Jason _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Martijn van Steenbergen-2
::
Rate this Message:
I suggest you all add your name and vote here:
http://doodle.com/4yrfd7qaw5man3rm Perhaps we'll find one of the options is clearly in favor. Martijn. Bryan O'Sullivan wrote: > I've thought for a while that it would be very nice indeed if the Monoid > class had a more concise operator for infix appending than "a `mappend` > b". I wonder if other people are of a similar opinion, and if so, > whether this is worth submitting a libraries@ proposal over. > > > ------------------------------------------------------------------------ > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@... > http://www.haskell.org/mailman/listinfo/haskell-cafe _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Robert Greayer-2
::
Rate this Message:
I'm sure there's some important historical reason... but why isn't '&'
used in something more prominent than the fgl package? I understand why it's not used for bitwise AND in Data.Bits (I assume because the corresponding bitwise '|' operator isn't available), but all the other single-character operators** (in the ASCII range) are used in some core library (if not the Prelude itself). But not '&'. Why? It makes sense (to me) as a Monoid 'append'. ** - according to Hoogle On Wed, Jul 1, 2009 at 10:46 AM, Edward Kmett<ekmett@...> wrote: > I'm rather fond of the (<>) suggestion, but would be happy with anything > better than mappend! ;) > > -Ed > > On Wed, Jul 1, 2009 at 8:56 AM, Brent Yorgey <byorgey@...> wrote: >> >> On Wed, Jul 01, 2009 at 12:00:50AM -0400, ajb@... wrote: >> > G'day all. >> >> > >> > On Tue, Jun 30, 2009 at 08:02:48PM -0400, Daniel Peebles wrote: >> > >> >> But we don't want to imply it's commutative either. Having something >> >> "bidirectional" like <> or <+> feels more commutative than associative >> >> to me. >> > >> > Quoting John Meacham <john@...>: >> > >> >> Not really, think of '++', which doesn't commute but is visually >> >> symmetric, or Data.Sequence.<>, or the common use of <> to mean >> >> concatination in pretty printers. >> > >> > Other good examples are && and ||. >> >> ..wha? But those ARE commutative. Unless you mean with respect to >> strictness? >> >> -Brent >> _______________________________________________ >> Haskell-Cafe mailing list >> Haskell-Cafe@... >> http://www.haskell.org/mailman/listinfo/haskell-cafe > > > _______________________________________________ > Haskell-Cafe mailing list > Haskell-Cafe@... > http://www.haskell.org/mailman/listinfo/haskell-cafe > > Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Ross Paterson
::
Rate this Message:
On Wed, Jul 01, 2009 at 04:53:05PM +0200, Thomas Davie wrote:
> > On 1 Jul 2009, at 16:46, Edward Kmett wrote: > >> I'm rather fond of the (<>) suggestion, but would be happy with >> anything better than mappend! ;) > > I find it rather ugly, it has a lot of connotations of "does not equals" > from other languages. Forget Pascal: think of it as a diamond. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by David Leimbach
::
Rate this Message:
On Wed, Jul 1, 2009 at 5:18 AM, Jules Bean <jules@...> wrote:
I like this thinking as well. I kind of wish Haskell didn't overload operators to begin with but oh well :-) Just because the compiler can figure out what I mean because it has a great type system, I might not be able to figure out what I mean a year from now if I see ++ everywhere.
In some sense, I prefer misleading function names to overly overloaded operators. Dave
_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Bryan O'Sullivan
::
Rate this Message:
On Wed, Jul 1, 2009 at 3:38 AM, Duncan Coutts <duncan.coutts@...> wrote:
Okay, here's a tentative plan that will help to figure out the answer. I'll build a fiddled base package that rewires the Monoid class to have (++) be the binary operator, and mappend as a synonym for it. I'll import the Monoid (++) into the Prelude. I'll see how much breaks. If that much builds smoothly, I'll see how much of the rest of Hackage builds, both with and without this custom base package. I'll follow up here with the results, along with a suggestion of how acceptable I think the observed level of breakage is. Seem reasonable? _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by David Leimbach
::
Rate this Message:
On Wed, Jul 1, 2009 at 10:55 AM, Bryan O'Sullivan <bos@...> wrote:
It's more reasonable than sitting around waxing philosophical on the notation I suppose :-)
_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
|
|
Re: Monoid wants a (++) equivalent
by Ross Paterson
::
Rate this Message:
On Wed, Jul 01, 2009 at 10:55:39AM -0700, Bryan O'Sullivan wrote:
> Okay, here's a tentative plan that will help to figure out the answer. I'll > build a fiddled base package that rewires the Monoid class to have (++) be the > binary operator, and mappend as a synonym for it. I'll import the Monoid (++) > into the Prelude. I'll see how much breaks. If that much builds smoothly, I'll > see how much of the rest of Hackage builds, both with and without this custom > base package. I'll follow up here with the results, along with a suggestion of > how acceptable I think the observed level of breakage is. Generalizing (++) will break some Haskell 98 code, e.g. append = (++) I think that's a show-stopper. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@... http://www.haskell.org/mailman/listinfo/haskell-cafe |
| < Prev | 1 - 2 - 3 - 4 | Next > |
| Free embeddable forum powered by Nabble | Forum Help |
