`ifL` isn't a legal lens for several reasons.
Lens s t a b generally requires that the types a subsumes b and b subsumes
a, and that s subsumes t and t subsumes s.
Lens s (Maybe t) (Maybe a) b is a huge red flag.
There is an 'illegal prism' provided by lens that is a more principled
version of
On Sun, Sep 29, 2013 at 8:20 AM, Edward Kmett ekm...@gmail.com wrote:
I don't know that it belongs in the standard libraries, but there could
definitely be a package for something similar.
ConstraintKinds are a pretty hefty extension to throw at it, and the
signature written
I don't know that it belongs in the standard libraries, but there could
definitely be a package for something similar.
ConstraintKinds are a pretty hefty extension to throw at it, and the
signature written there prevents it from being used on ByteString, Text,
etc.
This can be implemented with
You can't write that lens by hand, so it isn't surprising that the template
haskell can't generate it either. =)
ImpredicativeTypes don't work all that well.
-Edward
On Sun, Sep 8, 2013 at 9:49 AM, Artyom Kazak y...@artyom.me wrote:
Here’s a small example, which, when compiled, gives an
Or fmap in this case =)
On Wed, Jul 31, 2013 at 11:33 AM, Erik Hesselink hessel...@gmail.comwrote:
On Fri, Jul 26, 2013 at 6:44 PM, Andreas Abel andreas.a...@ifi.lmu.de
wrote:
mapSnd f = (id *** f)
As a very small aside, this is just `second` from Control.Arrow.
Erik
I'm just going to say that I'd rather we didn't resort to calling each
others trolls.
I happen to disagree with Oleg on this particular issue and find that it is
better resolved by just using -Wall or a 2-line combinator, but I find that
across the breadth and depth of issues in the Haskell
is a lazy constructor.
On 22.07.13 4:54 PM, Edward Kmett wrote:
let x = x +1
is perfectly cromulent when x is sufficiently lazy, e.g. in the one point
compactification of the naturals:
data Conat = S Conat | Z
There it represents infinity with proper sharing.
-Edward
On Jul 22, 2013
let x = x +1
is perfectly cromulent when x is sufficiently lazy, e.g. in the one point
compactification of the naturals:
data Conat = S Conat | Z
There it represents infinity with proper sharing.
-Edward
On Jul 22, 2013, at 10:24 AM, Andreas Abel andreas.a...@ifi.lmu.de wrote:
On
This happened because I copied the surrounding style blindly. I fucked up.
state f = get = \s - case f s of
(a, s) - do
put s
return a
would not have the problem and would have given a warning about name
shadowing.
I for one am somewhat neutral on the *adding* a non-recursive let
FWIW, I maintain, according to wc and sloccount, 220841 lines worth of
Haskell code at present.
I have been bitten this error one time, so it affects me .45% of the
time and that was only because it was in the only package I was not using
-Wall on.
-Edward
On Wed, Jul 17, 2013 at 12:23 PM,
On Wed, Jul 10, 2013 at 3:47 AM, o...@okmij.org wrote:
Jon Fairbairn wrote:
It just changes forgetting to use different variable names because of
recursion (which is currently uniform throughout the language) to
forgetting to use non recursive let instead of let.
Let me bring to the
, Carter Schonwald wrote:
Yup. Nested cases *are* non recursive lets.
(Can't believe I forgot about that )
On Thursday, July 11, 2013, Edward Kmett wrote:
On Wed, Jul 10, 2013 at 3:47 AM, o...@okmij.org javascript:_e({},
'cvml', 'o...@okmij.org'); wrote:
Jon Fairbairn
The getting to know your mentor period has passed and the Summer of Code
has officially begun.
Keep in mind that mid-term evaluations will begin July 29th, so students
will need to hit the ground running.
I'm looking forward to seeing what we can accomplish together this year!
-Edward
but there may be a free equivalent
Dominic Steinitz
domi...@steinitz.org
http://idontgetoutmuch.wordpress.com
On 28 May 2013, at 16:11, Edward Kmett ekm...@gmail.com wrote:
Hi Dominic,
The proposal is admittedly rather unfortunately opaque.
The parts I can shed light on:
Students come
There should be a link from the google-melange website, but one slight
shift in focus is on either getting SWIG bindings or possibly even using
Ian-Woo Kim's C++FFI tools. Carter may be able to go into more detail.
On Wed, May 29, 2013 at 6:46 AM, harry volderm...@hotmail.com wrote:
Edward
per se but it is good
to keep such a concrete goal in mind when working on something as abstract
as SWIG.
I agree that Qt has a somewhat horrible API. =)
-Edward
On Wed, May 29, 2013 at 12:34 PM, harry volderm...@hotmail.com wrote:
Edward Kmett ekmett at gmail.com writes:
There should
or if my answer didn't
suffice please feel free to follow up!
-Edward Kmett
On Tue, May 28, 2013 at 6:52 AM, Dominic Steinitz domi...@steinitz.orgwrote:
Hi Edward,
Although the project I am interested in (as a user) has been accepted :-),
I can't help feeling the selection process is a bit
of such a proposal that we've had in recent years.
-Edward
On Tue, May 28, 2013 at 8:24 PM, Ben Lippmeier b...@ouroborus.net wrote:
On 29/05/2013, at 1:11 AM, Edward Kmett wrote:
This unfortunately means, that we can't really show the unaccepted
proposals with information about how to avoid
.
Shachaf Ben-Kiki is helping out as this year's backup administrator and he
should also be able to help out with administrivia or questions as well.
I'd like to thank everyone for participating in the selection process and I
think we can look forward to another excellent summer of code!
Edward Kmett
There is a chicken and the egg problem with this argument.
Historically Haskell' has only considered changes that have been actually
implemented.
I would encourage the language standard to follow suit, but we survived a
similar autocratic minor change to Num with very little ecosystem
Tantamount to a new language to fix a minor detail in a typeclass
hierarchy? That is just histrionic. *No* language is that stable.
Scala makes dozens of changes like that between *minor* versions, and while
I hardly hold up their development practices as the best in the industry it
is still
So basically it boiled down drop the haskell98 package dependency and use
the new exception system, and import the right things to avoid the use of
the no longer exported Prelude catch?
On Fri, May 3, 2013 at 12:44 PM, Niklas Hambüchen m...@nh2.me wrote:
While I certainly enjoy the discussion,
That is because every other language conflates the notion of a class with a
vtable smashed into every inhabitant of the class where everything has to
be defined together in one monolithic definition.
You also can't write sensible Monads in those languages (Where does return
go?) or retroactively
Apr 2013, at 23:03, Edward Kmett ekm...@gmail.com wrote:
hmatrix and ad don't (currently) mix.
The problem is that hmatrix uses a packed structure that can't hold any of
the AD mode variants we have as an Element. =(
I've been working with Alex Lang to explore in ad 4.0 ways that we can
hmatrix and ad don't (currently) mix.
The problem is that hmatrix uses a packed structure that can't hold any of
the AD mode variants we have as an Element. =(
I've been working with Alex Lang to explore in ad 4.0 ways that we can
support monomorphic AD modes and still present largely the same
to pester me (or Shachaf) with questions!
-Edward Kmett
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Konstantin,
Please allow me to elaborate on Dan's point -- or at least the point that I
believe that Dan is making.
Using,
let bug = Control.DeepSeq.rnf str `seq` fileContents2Bug str
or ($!!) will create a value that *when forced* cause the rnf to occur.
As you don't look at bug until much
Actually Control.Lens.Getter doesn't use TH. The issue is more that it
depends on some modules I didn't flag as Trustworthy and which require some
more high-falutin type system extensions that GHC isn't happy about
treating as Safe. I'll try adding a few Trustworthy flags.
It previously was
in the event of Trustworthy.
Particularly fancy if integrated into the haddocks.
-mgsloan
On Mon, Oct 29, 2012 at 2:33 PM, Edward Kmett ekm...@gmail.com wrote:
Actually Control.Lens.Getter doesn't use TH. The issue is more that it
depends on some modules I didn't flag as Trustworthy and which
future accidental
toggleage. Still, it's puzzling that the status of Safe-Infered was
lost.
On Mon, Oct 29, 2012 at 2:46 PM, Edward Kmett ekm...@gmail.com wrote:
I fixed it. Version 3.0.6 was just uploaded to hackage and is
appropriately
Trustworthy where needed.
Please let me know if I
Was there some significant change/bug introduced to haddock made between
2.10 and 2.12?
When I look at the haddocks for kan-extensions 3.1:
Data.Functor.Yonedahttp://hackage.haskell.org/packages/archive/kan-extensions/3.1/doc/html/Data-Functor-Yoneda.html
which
purports to have been built by
Here is a considerably longer worked example using the analogy to J,
borrowing heavily from Wadler:
As J, this doesn't really add any power, but perhaps when used with
non-representable functors like Equivalence/Comparison you can do something
more interesting.
-- Used for Hilbert
{-# LANGUAGE
As an aside, the Union constraint on epsilon/gepsilon is only needed for
the :+: case, you can search products just fine with any old contravariant
functor, as you'd expect given the existence of the Applicative.
-Edward
On Sat, Jun 9, 2012 at 6:28 PM, Edward Kmett ekm...@gmail.com wrote:
Here
I'll need to get an older ghc version installed, so I can try to figure out
what changes are needed to make template haskell bits compatible back to the
current platform. 'ad' uses TH rather extensively, and sadly, the update to
support ghc 7.4.1 broke a fair bit of the old code gen -- as I
It depends on how you are building the tree.
If you are building up the tree from repeated substitution at the leaves
and never reference its body before you do the final fold, you may be able
to exploit the fact that trees form a free monad, and that there is a nice
construction for increasing
very much and we look forward to another successful Summer of
Code!
-Edward Kmett
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Just to clarify, since I've been getting a ton of emails on the topic, we
*have* been accepted to the Google Summer of Code this year.
The list on their site is still updating, and we should appear there
shortly.
-Edward
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, 2011 at 2:07 PM, Edward Kmett ekm...@gmail.com wrote:
Jason,
Thank you for taking ownership of HOpenGL!
Thanks!
I would like to make a formal request for there to be some way to get
access
to either
Graphics.Rendering.OpenGL.Raw.Core31.TypesInternal
Jason,
Thank you for taking ownership of HOpenGL!
I would like to make a formal request for there to be *some* way to get
access to either
Graphics.Rendering.OpenGL.Raw.Core31.TypesInternal
or that
Graphics.Rendering.OpenGL.Raw.Core31.Types
re-export the newtype wrappers it places around
://haskell.org/haskellwiki/Hac_Boston/Talks
.
We look forward to seeing you at MIT!
-Edward Kmett
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Correction: January 20-22nd ;)
On Tue, Oct 25, 2011 at 5:45 PM, Edward Kmett ekm...@gmail.com wrote:
I am very pleased to officially announce Hac Boston, a Haskell hackathon
to be held January 21-23, 2012 at MIT in Cambridge, MA.
The hackathon will officially kick off at 2:30 Friday
haven't bundled it up
for third party use yet, but its *my* practice. ;)
-Edward Kmett
This is what I've been looking at lately. The first thing I noticed
was the GNU gettext implementation for Haskell. The wiki page [1] has
a nice explanation by Aufheben. The hgettext package is found here
[2
You still need IO to get the stable name out to use. :)
Sent from my iPad
On Sep 23, 2011, at 5:33 AM, Sean Leather leat...@cs.uu.nl wrote:
Hi Edward,
On Thu, Sep 22, 2011 at 16:50, Edward Kmett wrote:
I have a stable-maps package that provides lookup and inserting into a map
via stable
Import Data.HashTable
import Data.Dynamic
table :: HashTable StableName Dynamic
table= new (==) hashStableName
2011/9/22 Edward Kmett ekm...@gmail.com
I have a stable-maps package that provides lookup and inserting into a map
via stable names.
-Edward
On Thu, Sep 22, 2011 at 5
I have a stable-maps package that provides lookup and inserting into a map
via stable names.
-Edward
On Thu, Sep 22, 2011 at 5:47 AM, Sean Leather leat...@cs.uu.nl wrote:
There is an abstract type called SNMap for stable names referred to in [1].
This has apparently disappeared from GHC a
Then don't do that. =) I should have mentioned, parametric keys are a no
no and can do bad things. ;)
-Edward
On Thu, Sep 22, 2011 at 2:33 PM, James Cook mo...@deepbondi.net wrote:
I may be wrong, but I think the original SNMap was a map from 'StableName's
to the specific values they were
On Sep 18, 2011, at 11:28 AM, Brandon Allbery allber...@gmail.com wrote:
On Sat, Sep 17, 2011 at 22:11, Anton Tayanovskyy
anton.tayanovs...@gmail.com wrote:
By the way, can Haskell have a type that admits regular expression and
only those? I mostly do ML these days, so trying to write up a
I originally didn't have the package exporting those things.
I would be amenable to standardization without them, but I use them in about
20 packages that are built on top of semigroups, and naturals and non-empty
lists come up when talking about semigroups a lot.
Rather than having them live
On Sun, Jul 3, 2011 at 11:05 AM, David Banas dba...@banasfamily.net wrote:
v0.4 of `RandProc` has just been posted to Hackage:
http://hackage.haskell.org/package/randproc
[NB: I transfered this discussion from haskell to haskell-cafe, and started
another thread]
I have been spending some
and Vene is packaged
in 'streams' as Data.Stream.Future:
http://hackage.haskell.org/packages/archive/streams/0.8.0/doc/html/Data-Stream-Future.html
-Edward Kmett
On Mon, Jun 20, 2011 at 10:45 AM, Richard Senington sc06...@leeds.ac.ukwrote:
Hi all,
I have recently become interested in Dataflow
interconvert to [a].
-Edward
On Tue, May 3, 2011 at 6:49 PM, Edward Kmett ekm...@gmail.com wrote:
On Tue, May 3, 2011 at 3:43 PM, Yitzchak Gale g...@sefer.org wrote:
Edward Kmett wrote:
sconcat :: [a] - a - a
with either the semantics you supplied or something like
sconcat = appEndo . mconcat
On Wed, May 4, 2011 at 7:40 AM, John Lato jwl...@gmail.com wrote:
From: Edward Kmett ekm...@gmail.com
On Tue, May 3, 2011 at 3:43 PM, Yitzchak Gale g...@sefer.org wrote:
I'm sure there are countless other natural examples of semigroups
in the wild, and that the typical non-trivial ones
On Tue, May 3, 2011 at 12:04 PM, Bryan O'Sullivan b...@serpentine.comwrote:
On Tue, May 3, 2011 at 8:00 AM, Yitzchak Gale g...@sefer.org wrote:
Could you please add a Semigroup instance for Text?
I'd strongly recommend writing an instance for the text package's Builder
type instead.
On Tue, May 3, 2011 at 7:12 AM, Yitzchak Gale g...@sefer.org wrote:
Hi Edward,
Thanks much for the very useful semigroups
package.
When using it in practice, it would be very useful
to have an analogue to the mconcat method of
Monoid. It has the obvious default implementation,
but allows
On Tue, May 3, 2011 at 3:43 PM, Yitzchak Gale g...@sefer.org wrote:
Edward Kmett wrote:
sconcat :: [a] - a - a
with either the semantics you supplied or something like
sconcat = appEndo . mconcat . map diff
The sconcat we have been discussing is
sconcat = flip $ appEndo . getDual
:49 PM, Edward Kmett ekm...@gmail.com wrote:
On Tue, May 3, 2011 at 3:43 PM, Yitzchak Gale g...@sefer.org wrote:
Edward Kmett wrote:
sconcat :: [a] - a - a
with either the semantics you supplied or something like
sconcat = appEndo . mconcat . map diff
The sconcat we have been
On Tue, Mar 29, 2011 at 1:26 PM, Rogan Creswick cresw...@gmail.com wrote:
I've been wanting to share code between cabal projects for some time,
and I finally had a chance to write up the rough idea as a simple
proposal. Here's the description, with links to the SoC trac and
reddit
2011/3/22 Mario Blažević mblaze...@stilo.com
This seems very interesting. One question:
The MonadPlus and the Alternative instance differ: the former's mplus
combinator equals the asymmetric | choice.
Why?
Good question. Basically, I see MonadPlus as a union of Monad and
If you add an instance of IsString to handle leaf construction you can get
it down to
Fruits + do
Apple
Mango
Arbitrary + do
1
...
But I also don't see the point of doing this in a monad.
-Edward
On Tue, Mar 22, 2011 at 1:15 PM, Yves Parès
21, 2011 at 4:57 PM, Edward Kmett ekm...@gmail.com wrote:
On Mon, Mar 21, 2011 at 2:42 PM, Edward Amsden eca7...@cs.rit.eduwrote:
So I'm feeling a bit elated that I've sparked my first theoretical
discussion in cafe, though I don't have much to contribute. :\
However in the interests
On Sun, Mar 20, 2011 at 5:46 PM, Tom Nielsen taniel...@gmail.com wrote:
Interval arithmetic is of course not the same as uncertainty, although
computer scientists like to pretend that is the case. (and uncertainty
estimates do not have the be rough.)
Very true.
In general the propagation
comment.
I've pushed a new version of intervals to mollify hackage.
It (or the old version) should cabal install just fine.
-Edward Kmett
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If your function has nice derivatives, you may want to look at the Newton
implementation in
http://hackage.haskell.org/packages/archive/ad/0.44.4/doc/html/Numeric-AD-Newton.html#v:findZero
http://hackage.haskell.org/packages/archive/ad/0.44.4/doc/html/Numeric-AD-Newton.html#v:findZeroor
if you
I have a package for interval arithmetic in hackage
http://hackage.haskell.org/package/intervals-0.2.0
However it does not currently properly adjust the floating point rounding
mode so containment isn't perfect.
However, we are actively working on fixing up the Haskell MPFR bindings,
which will
!
-Edward Kmett
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Clearly we need some sort of xbox live -like achievement system for these.
Achievement Unlocked: Stumped Oleg!
On Sat, Feb 12, 2011 at 6:57 PM, Jan Christiansen
j...@informatik.uni-kiel.de wrote:
On 12.02.2011, at 21:18, Aaron Gray wrote:
I was wondering if anyone had an idea or estimate
On Thu, Mar 17, 2011 at 6:41 PM, wren ng thornton w...@freegeek.org wrote:
On 3/17/11 5:12 PM, Conor McBride wrote:
On 17 Mar 2011, at 18:35, wren ng thornton wrote:
Another question on particulars. When dealing with natural numbers, we
run into the problem of defining subtraction. There
On Wed, Mar 9, 2011 at 6:21 PM, Yves Parès limestr...@gmail.com wrote:
Well, I want to hide the fact that I'm using ST, so if I can hide the
existential type 's' it is better.
In practice if you want to actually _use_ ST you'll find you'll need to let
the world escape into your type.
repository up to date?
-Edward Kmett
On Fri, Mar 4, 2011 at 3:27 PM, Daniel Peebles pumpkin...@gmail.com wrote:
According to Duncan Coutts (whom I asked about this issue in #ghc), the
solution here is to use the new foreign import prim machinery to talk to
MPFR. This prevents GC from occurring during
that were blocked by this.
-Edward Kmett
2011/3/3 Michal Konečný m...@konecny.aow.cz
Dear all,
I am pleased to announce hmpfr-0.3.2, a new version of Aleš Bizjak's
bindings
to the MPFR arbitrary precision floating point arithmetic library. The
changes in this version are quite small
On Sat, Feb 19, 2011 at 7:27 PM, Sterling Clover s.clo...@gmail.com wrote:
On Sat, Feb 19, 2011 at 3:04 PM, Johan Tibell johan.tib...@gmail.com
wrote:
On Sat, Feb 19, 2011 at 11:58 AM, Louis Wasserman
wasserman.lo...@gmail.com wrote:
A couple thoughts:
size takes O(n). That's just
I would happily supply a patch to add the Typeable (and the few Data
instances that can be made) to transformers. I had to make similar ones in
my comonad-transformers package anyways.
-Edward Kmett
On Wed, Feb 2, 2011 at 1:02 AM, John Millikin jmilli...@gmail.com wrote:
Is there any
+1 for adding a Contrafunctor/ContraFunctor to base somewhere. But I agree
completely with Tony, please call it contramap. ;) Otherwise people will
wonder why comonads are not cofunctors -- a matter which can be cleared up
by avoiding sloppy terminology.
+1 for adding Comonads. As an aside, since
that function
using the approach you used will lead to a computation that won't terminate.
-Edward Kmett
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is the associativity of Kleisli arrow composition and the two
identity laws.
The three monad laws are precisely what you need to form this monoid. There
are analogous laws for Applicative that serve the same purpose.
-Edward Kmett
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runhaskell Setup.hs foo instead of
cabal foo. You just need to tell cabal if you want to delegate to Setup.hs,
by using something other than Simple as a build-type. The vast majority of
the users of cabal never bother changing the behavior of Setup.hs.
-Edward Kmett
On Thu, Jul 22, 2010 at 11:58 PM
On Fri, Jul 23, 2010 at 8:07 AM, Edward Kmett ekm...@gmail.com wrote:
That actually runs contrary to one of cabal's other practices, which is to
add a 'simple' Setup.hs to your package as it makes the sdist is one is not
present.
er.. I meant if one is not present
mechanism. That way hot-swapping the current process would
leave your GUI (and the pipe/IPC mechanism) intact.
You may then need to pass along whatever changes affect the gui over the
pipe in a fairly manual fashion.
-Edward Kmett
On Thu, Jul 15, 2010 at 11:05 PM, Andy Stewart lazycat.mana
of overloading and polymorphic
instantiation in Haskell, e.g. dealing with portfolios that span multiple
currencies, so take care with shackling yourself to the current design.
-Edward Kmett
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http
' 1230891823091823018203123
93721573993600178112200489
*Main fastest_f' 12308918230918230182031231231293810923
11097012733777002208302545289166620866358
-Edward Kmett
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a good idea to either filter the negative
case like you do here, or, since it is well defined, extend the scope of the
memo table to the full Int range by explicitly memoizing negative vales as
well.
-Edward Kmett
On Fri, Jul 9, 2010 at 11:51 AM, Mike Dillon m...@embody.org wrote:
begin Edward
On Thu, Jul 8, 2010 at 12:37 PM, Yitzchak Gale g...@sefer.org wrote:
Hi Edward,
Edward Kmett wrote:
It looks like there is a fairly strong effort to fix most of the most
egregious warts in the mtl.
btw, does this overhaul include adding Applicative instances,
perchance
could prove or disprove. ;-)
I hope the above demonstrate that there are at least some fairly reasonable
(and, given your request, appropriately category theoretic!) examples where
one would want the ability to specify that there is more than one member of
a minimal mutual definition. =)
-Edward
flipping its lid.
Of course, adding support for monadLib, which doesn't conflict with any of
this is a completely concern.
-Edward Kmett
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we're on the topic, does anyone else get funny looks when they say
monads?
Sadly, yes. ;)
-Edward Kmett
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On Tue, Jul 6, 2010 at 10:01 PM, Ertugrul Soeylemez e...@ertes.de wrote:
Edward Kmett ekm...@gmail.com wrote:
You may want to review the thread here:
http://www.haskell.org/pipermail/libraries/2009-November/012833.html
The gist of it is, I would recommend sticking with MTL for right
or ways to implement memoization in a purely
functional setting, or how to abuse side effects to do so in a less pure
way. Those are the kinds of things you get exposed to through actually using
Haskell, rather than through reading a monad tutorial.
-Edward Kmett
.
This much works. However equality constraints in the body still blow up at
last check.
-Edward Kmett
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with.
Typically you can construct something purely and inspect the result using IO
all in one go, so the unsafePerformIO machinery isn't required.
-Edward Kmett
2010/6/28 José Romildo Malaquias j.romi...@gmail.com
Is there in Haskell a non monadic function of type a - a - Bool which
test
that Codensity Reader ~ State.
Take a look at the code in monad-ran on hackage for how Ran (StateT s m) is
implemented for an example.
-Edward Kmett
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to have the constraint Y d. The above code
then stays the same, only with Yoneda removed and constraints added.
This is an encoding of the fact that all Functors in Haskell are strong, and
that Yoneda i is a Functor for any i :: * - *.
-Edward Kmett
On Sun, Jun 27, 2010 at 6:45 PM, Max Bolingbroke batterseapo...@hotmail.com
wrote:
On 27 June 2010 22:20, Edward Kmett ekm...@gmail.com wrote:
I've pointed out the Codensity Set monad on the Haskell channel.
I spend no time on #haskell but clearly I should :)
It is an
interesting
this time around.
I will check with him to see if I can get permission to host them somewhere
and post a link to them here.
-Edward Kmett
On Fri, Jun 25, 2010 at 5:04 AM, corentin.dup...@ext.mpsa.com wrote:
Hello Haskellers,
I'm having trouble writing a Read Instance for my GATD.
Arg this GATD
I've obtained permission to repost Gershom's slides on how to deserialize
GADTs by typechecking them yourself, which are actually a literate haskell
source file, that he was rendering to slides. Consequently, I've just pasted
the content below as a literate email.
-Edward Kmett
-
Deserializing
the other way.
-Edward Kmett
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On Wed, Jun 23, 2010 at 2:57 PM, Gregory Crosswhite
gcr...@phys.washington.edu wrote:
On 6/23/10 2:13 PM, Edward Kmett wrote:
On Tue, Jun 22, 2010 at 4:54 PM, Gregory Crosswhite
gcr...@phys.washington.edu wrote:
There is no reason that your program couldn't link to multiple versions
What you're looking for is something like:
deriveVariable _t = [d|
instance Variable $t where
toVariant = toVariant . show
fromVariant x = fmap (\v - read v :: $t) $ fromVariant x|]
deriveVariable (conT ''PageType)
deriveVariable (conT ''Int)
deriveVariable (conT ''Maybe
v-- I had accidentally elided the _'s before the t's in the quasiquotation
before.
What you're looking for is something like:
deriveVariable _t = [d|
instance Variable $_t where
toVariant = toVariant . show
fromVariant x = fmap (\v - read v :: $_t) $ fromVariant x|]
are not the answer.
-Edward Kmett
On Tue, Jun 8, 2010 at 2:21 PM, Gregory Crosswhite
gcr...@phys.washington.edu wrote:
Or you just put an upper bound on the versions of the fgl library that your
program will build against, as you should be doing anyway, and then nothing
breaks.
Cheers,
Greg
On Jun 8
://hackage.haskell.org/packages/archive/monoids/0.1.36/doc/html/src/Data-Generator-Compressive-LZ78.html
-Edward Kmett
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