universum
Custom prelude used in Serokell
https://github.com/serokell/universum
LTS Haskell 22.33: | 1.8.2.1 |
Stackage Nightly 2024-09-07: | 1.8.2.1 |
Latest on Hackage: | 1.8.2.1 |
universum-1.8.2.1@sha256:3927ea492426eaf0aba7a5914c4beb109b11802171df095147cbf873ef34d5b9,6689
Module documentation for 1.8.2.1
- Universum
- Universum.Applicative
- Universum.Base
- Universum.Bool
- Universum.Container
- Universum.Debug
- Universum.DeepSeq
- Universum.Exception
- Universum.Function
- Universum.Functor
- Universum.Lifted
- Universum.List
- Universum.Monad
- Universum.Monoid
- Universum.Nub
- Universum.Print
- Universum.String
- Universum.TypeOps
- Universum.Unsafe
- Universum.VarArg
Universum
universum
is a custom prelude used in @Serokell that has:
- Excellent documentation: tutorial, migration guide from
Prelude
, Haddock with examples for (almost) every function, all examples are tested withdoctest
, documentation regarding internal module structure. universum
-specific HLint rules:.hlint.yaml
- Focus on safety, convenience and efficiency.
What is this file about?
This README contains introduction to Universum
and a tutorial on how to use it.
Structure of this tutorial
This tutorial has several parts:
- Philosophy and motivation.
- How to use
universum
. - Changes in
Prelude
(some gotchas). - Already known things that weren’t in
Prelude
brought into scope. - New things added.
- Migration guide from
Prelude
.
This is neither a tutorial on Haskell nor tutorial on each function contained in Universum. For detailed documentation of every function together with examples and usage, see Haddock documentation.
Why another custom Prelude? ↑
Motivation
At Serokell, we strive to be as productive as possible. That’s why we are using Haskell. This choice of language implies
that we’re restricted to use Prelude
:
implicit import of basic functions, type classes and data types. Unfortunately, the default Prelude
is considered to be not so good
due to some historical reasons.
This is why we decided to use a better tool. Luckily, Haskell provides us with the ability
to replace default Prelude
with an alternative. All we had to do is to implement a
new basic set of defaults. There already were plenty of preludes,
so we didn’t plan to implement everything from scratch.
After some long, hot discussions, our team decided to base our custom prelude on
protolude
. If you’re not familiar with it,
you can read a tutorial about protolude
.
The next section explains why we’ve made this choice and what we are willing to do.
This tutorial doesn’t cover the differences from protolude
. Instead, it explains how Universum is different from regular Prelude
.
Main goals
While creating and maintaining a custom prelude, we are pursuing the following goals:
- Avoid all partial functions.
We like total and exception-free functions.
You can still use some unsafe functions from
Universum.Unsafe
module, but they are not exported by default. - Use more efficient string representations.
String
type is crushingly inefficient. All our functions either try to be polymorphic over string type or useText
as the default string type. Because the community is evolving slowly, some libraries still useString
type, soString
type alias is still reexported. We recommend to avoidString
as much as you can! - Try to not reinvent the wheel. We’re not trying to rebuild whole type hierarchy from scratch,
as it’s done in
classy-prelude
. Instead, we reexport common and well-known things frombase
and some other libraries that are used in everyday production programming in Haskell.Note: well, we did end up inventing some new things.
- Export more useful and commonly used functions. Hello, my name is Dmitry. I was
coding Haskell for 3 years but still hoogling which module
liftIO
comes from. Things likeliftIO
,ReaderT
type,MVar
-related functions have unambiguous names, are used in almost every non-trivial project, and it’s really tedious to import them manually every time. - Make changes only when there are enough good reasons to make these changes. We have a code modification policy which semi-formally describes pre-conditions for different types of changes.
Unlike protolude
, we are:
- Not trying to be as general as possible (thus we don’t export much from
GHC.Generics
). - Not trying to maintain every version of
ghc
compiler (but at least the latest 3). - Trying to make writing production code easier (see enhancements and fixes).
How to use Universum ↑
Okay, enough philosophy. If you want to just start using universum
and
explore it with the help of compiler, set everything up according to the instructions below.
Disable the built-in prelude at the top of your file:
{-# LANGUAGE NoImplicitPrelude #-}
Or directly in your project .cabal
file, if you want to use in every module by default:
default-extensions: NoImplicitPrelude
Then add the following import to your modules:
import Universum
If you’re using Emacs and don’t want to
type import Universum
manually every time, you can
modify your configs
a little bit.
If you want to get familiar with universum
internal structure, you can just
read top-level documentation for
Universum
module.
Gotchas ↑
head
,tail
,last
,init
,foldl1
,minimum
and other were-partial functions work withNonEmpty a
instead of[a]
.- Safe analogue for
head
,foldl1
,foldr1
,minimum
,maximum
functions, for instance:safeHead :: [a] -> Maybe a
. undefined
triggers a compiler warning, which is probably not what you want. Either usethrowIO
,Except
,error
orbug
.map
isfmap
now.- Multiple sorting functions are available without imports:
sortBy :: (a -> a -> Ordering) -> [a] -> [a]
: sorts list using given custom comparator.sortWith :: Ord b => (a -> b) -> [a] -> [a]
: sorts a list based on some property of its elements.sortOn :: Ord b => (a -> b) -> [a] -> [a]
: just likesortWith
, but more time-efficient if function is calculated slowly (though less space-efficient). So you should writesortOn length
(would sort elements by length) butsortWith fst
(would sort list of pairs by first element).
- Functions
sum
andproduct
are strict now, which makes them more efficient. - If you try to do something like
putStrLn "hi"
, you’ll get an error message ifOverloadedStrings
is enabled – it happens because the compiler doesn’t know what type to infer for the string. UseputTextLn
in this case. - Since
show
doesn’t come fromShow
anymore, you can’t writeShow
instances easily. See migration guide for details. - You can’t call some
Foldable
methods overMaybe
and some other types.Foldable
generalization is useful but potentially error-prone. Instead we created our own fully compatible withFoldable
Container
type class but that restricts the usage of functions likelength
overMaybe
,Either
,Identity
and tuples. We’re also using GHC 8 feature of custom compile-time errors to produce more helpful messages. - As a consequence of previous point, some functions like
traverse_
,forM_
,sequenceA_
, etc. are generalized overContainer
type classes. error
takesText
.- We are exporting a rewrite rule which replaces
toString . toText :: Text -> Text
withid
. Note that this changes semantics in some corner cases.
Things that you were already using, but now you don’t have to import them explicitly ↑
Commonly used libraries
First of all, we reexport some generally useful modules: Control.Applicative
,
Data.Traversable
, Data.Monoid
, Control.DeepSeq
, Data.List
, and lots of others.
Just remove unneeded imports after importing Universum
(GHC should tell you which ones).
Then, some commonly used types: Map/HashMap/IntMap
, Set/HashSet/IntSet
, Seq
, Text
and ByteString
(as well as synonyms LText
and LByteString
for lazy versions).
liftIO
and MonadIO
are exported by default. A lot of IO
functions are generalized to MonadIO
.
deepseq
is exported. For instance, if you want to force deep evaluation of some value (in IO),
you can write evaluateNF a
. WHNF evaluation is possible with evaluateWHNF a
.
We also reexport big chunks of these libraries: mtl
, stm
, microlens
, microlens-mtl
.
Bifunctor
type class with useful instances is exported.
first
andsecond
functions apply a function to first/second part of a tuple (for tuples).bimap
takes two functions and applies them to first and second parts respectively.
Text
We export Text
and LText
, and some functions work with Text
instead of String
–
specifically, IO functions (readFile
, putStrLn
, etc) and show
. In fact, show
is polymorphic and can produce strict or lazy Text
, String
, or ByteString
.
Also, toText/toLText/toString
can convert Text|LText|String
types to Text/LText/String
. If you want to convert to and from ByteString
use encodeUtf8/decodeUtf8
functions.
Debugging and undefined
s
trace
, traceM
, traceShow
, etc. are available by default. GHC will warn you
if you accidentally leave them in code, however (same for undefined
).
We also have data Undefined = Undefined
(which, too, comes with warnings).
Exceptions
We use safe-exceptions
library for exceptions handling. Don’t import Control.Exceptions
module explicitly. Instead use functionality from safe-exceptions
provided by universum
or import Control.Exceptions.Safe
module.
What’s new? ↑
Finally, we can move to part describing the new cool features we bring with universum
.
-
uncons
splits a list at the first element. -
ordNub
andsortNub
are O(n log n) versions ofnub
(which is quadratic) andhashNub
andunstableNub
are almost O(n) versions ofnub
. -
(&)
– reverse application.x & f & g
instead ofg $ f $ x
is useful sometimes. -
whenM
,unlessM
,ifM
,guardM
are available and do what you expect them to do (e.g.whenM (doesFileExist "foo")
). -
Very generalized version of
concatMapM
, too, is available and does what expected. -
readMaybe
andreadEither
are likeread
but total and give eitherMaybe
orEither
with parse error. -
when(Just|Nothing|Left|Right|NotEmpty)[M][_]
let you conditionally execute something. Before:case mbX of Nothing -> return () Just x -> ... x ...
After:
whenJust mbX $ \x -> ... x ...
-
for_
for loops. There’s alsoforM_
butfor_
looks a bit nicer.for_ [1..10] $ \i -> do ...
-
andM
,allM
,anyM
,orM
are monadic version of corresponding functions frombase
. -
Type operator
$
for writing types likeMaybe $ Either String $ Maybe Int
. -
Each
type family. So this:f :: Each [Show, Read] [a, b] => a -> b -> String
translates into this:
f :: (Show a, Show b, Read a, Read b) => a -> b -> String
-
With
type operator. So this:a :: With [Show, Read] a => a -> a
translates into this:
a :: (Show a, Read a) => a -> a
-
Variadic composition operator
(...)
. So you can write:ghci> (show ... (+)) 1 2 "3" ghci> show ... 5 "5" ghci> (null ... zip5) [1] [2] [3] [] [5] True ghci> let process = map (+3) ... filter ghci> process even [1..5] [5,7]
-
Conversions between
Either
andMaybe
likerightToMaybe
andmaybeToLeft
with clear semantic. -
using(Reader|State)[T]
functions as aliases forflip run(Reader|State)[T]
. -
One
type class for creating singleton containers. Even monomorhpic ones likeText
. -
evaluateWHNF
andevaluateNF
functions as clearer and lifted aliases forevaluate
andevaluate . force
. -
ToPairs
type class for data types that can be converted to list of pairs (likeMap
orHashMap
orIntMap
).
Migration guide from Prelude ↑
In order to replace default Prelude
with universum
you should start with instructions given in
how to use universum section.
This section describes what you need to change to make your code compile with universum
.
-
Enable
-XOverloadedStrings
and-XTypeFamilies
extension by default for your project. -
Since
head
,tail
,minimum
and some other functions work forNonEmpty
you should refactor your code in one of the multiple ways described below:- Change
[a]
toNonEmpty a
where it makes sense. - Use functions which return
Maybe
. They can be implemented usingnonEmpty
function. Likehead <$> nonEmpty l
.head <$> nonEmpty l
issafeHead l
tail
isdrop 1
. It’s almost never a good idea to usetail
fromPrelude
.
- Add
import qualified Universum.Unsafe as Unsafe
and replace function with qualified usage.
- Change
-
If you use
fromJust
or!!
you should use them fromimport qualified Universum.Unsafe as Unsafe
. -
Derive or implement
Container
instances for your data types which implementFoldable
instances. This can be done in a single line becauseContainer
type class automatically derives fromFoldable
. -
Container
type class fromuniversum
replacesFoldable
and doesn’t have instances forMaybe a
,(a, b)
,Identity a
andEither a b
. If you usefoldr
orforM_
or similar for something likeMaybe a
you should replace usages of such function with monomorhpic alternatives:-
Maybe
(?:) :: Maybe a -> a -> a
fromMaybe :: a -> Maybe a -> a
maybeToList :: Maybe a -> [a]
maybeToMonoid :: Monoid m => Maybe m -> m
maybe :: b -> (a -> b) -> Maybe a -> b
whenJust :: Applicative f => Maybe a -> (a -> f ()) -> f ()
whenJustM :: Monad m => m (Maybe a) -> (a -> m ()) -> m ()
-
Either
fromLeft :: a -> Either a b -> a
fromRight :: b -> Either a b -> b
either :: (a -> c) -> (b -> c) -> Either a b -> c
whenRight :: Applicative f => Either l r -> (r -> f ()) -> f ()
whenRightM :: Monad m => m (Either l r) -> (r -> m ()) -> m ()
-
-
If you have types like
foo :: Foldable f => f a -> a -> a
you should chose one of the following:Right
: Modify types forContainer
likefoo :: (Container t, Element t ~ a) => t -> a -> a
.Left
: ImportData.Foldable
modulequalified
and use everythingFoldable
-related qualified.
-
Forget about
String
type.- Replace
putStr
andputStrLn
withputText
andputTextLn
. - Replace
(++)
with(<>)
forString
-like types. - Try to use
fmt
library if you need to construct messages. - Use
toText/toLText/toString
functions to convert toText/LazyText/String
types. - Use
encodeUtf8/decodeUtf8
to convert to/fromByteString
.
- Replace
-
Run
hlint
using.hlint.yaml
file fromuniversum
package to cleanup code and imports. -
Since vanilla
show
from theShow
class is not available, your customShow
instances will fail to compile. You canimport qualified Text.Show
to bring vanillashow
to scope with qualified name. It will not conflict withshow
fromuniversum
and yourShow
instances will compile successfully.
Changes
1.8.2.1
- #293
- Add explicit kind signatures for custom operators.
- Bump some dependency constraints to support GHC-9.8.
1.8.2
- #289:
Make universum work with LTS-21.0.
- Re-export
(~)
type operator.
- Re-export
- #283:
Bump the upper version bound on
text
to2.0.2
.
1.8.1.1
- #282:
Bump the upper version bound on
text
to2.0.1
.
1.8.1
- #271: Add compatibility with tasty-hedgehog 1.2.0.0
1.8.0
-
#252: Remove
Option
re-export. UseMaybe
instead. -
#176: Deprecate
note
. -
#206: Remove
listToMaybe
. Migration guide: usesafeHead
directly with functions fromUniversum.Container
instead. -
#182: Deprecate
microlens
andmicrolens-mtl
dependencies. -
#165: Change the type of
readMaybe
fromreadMaybe :: Read a => String -> Maybe a
to it’s polymorphic versionreadMaybe :: forall b a. (ToString a, Read b) => a -> Maybe b
. -
#199: Change type of
concatMap
fromconcatMap :: Foldable f => (a -> [b]) -> t a -> [b]
toconcatMap :: Container c => (Element c -> [b]) -> c -> [b]
. -
250: Replace
group
export fromData.List
withgroup
,groupBy
,groupWith
andgroupAllWith
fromData.List.NonEmpty
.
1.7.3
-
#236: Add
updateMVar'
andupdateTVar'
. -
#244 Add
ToPairs
instances for[(k, v)]
andNonEmpty (k, v)
. -
#238: Add
fromList
.
1.7.2 (rev1)
- Permit
text-1.2.5.0
.
1.7.2
- Permit
text-1.2.4.1
. - #233:
Add
someNE
.
1.7.1
1.7.0
- #221:
Add safe versions of
minimum
,maximum
,minimumBy
,maximumBy
,foldr1
,foldl1
functions forNonEmpty
list. Old their versions fromContainer
typeclass now returnMaybe
and havesafe
prefix in name (e.g.safeMinimum
). Add unsafe versions of those functions toUnsafe
module. - #185: Enable more warnings, fix all warnings.
1.6.1
- #219:
Bump upper bound on
text
.
1.6.0
-
#207: Remove various monad transformer combinators,
flipfoldl'
, and<<$>>
from the list of changes suggested in.hlint.yaml
. -
#214: Update supported GHC versions (replace 7.10.3 with 8.6.5).
-
#212 Added rewrite rule for
toString . toText
case. This may change semantics in some corner cases (becausetoString . toText
is not strictly the identity function). -
#215: Fix docstrings in
Universum.Lifted.File
to mention correct module when referencing related functions.
1.5.0
-
Make
error
’s stacktrace exclude site of theerror
function itself. -
#200: Implemented a lifted version of
withFile
and addedhClose
toUniversum.Lifted.File
as discussed previously in #186. -
#204: Make
trace
non-polymorphic over text argument, addtraceIdWith
andtraceShowIdWith
. -
#197
hPutStr
,hPutStrLn
andhPrint
added toUniversum.Print
. The interface for the backing typeclassUniversum.Print.Print
changed. It was also moved to the internal moduleUniversum.Print.Internal
and should be considered unstable.Migration guide: The interface for the
Print
class should be considered internal and may be subject to sudden change. If you must implement your own instances, then importUniversum.Print.Internal
(be aware that there are name clashes in the functions fromUniversum.Print
andUniversum.Print.Internal
) -
#201 Generalized the type of
Universum.Lifted.Env.die
. Should not break existing code, apart from, perhaps, type inference.
1.4.0
-
#167:
identity
has been removed.Migration guide: use
Universum.id
instead. -
#177: The
mask_
reexport fromsafe-exceptions
has been removed.Migration guide: use
Control.Exception.Safe.mask_
fromsafe-exceptions
instead. -
#178:
getArgs
has been removed.Migration guide: use
liftIO
directly withSystem.Environment.getArgs
from base. -
#179:
getContents
andinteract
have been removed.Migration guide: use
liftIO
directly withData.Text.Lazy.IO.getContents
andData.Text.Lazy.IO.interact
, both from thetext
package. -
#180: The
Lifted.ST
module has been removed.Migration guide: use
liftIO
directly with functions fromControl.Monad.ST
instead. -
#181:
list
has been removed.
1.3.0
-
#167:
identity
has been deprecated.Migration guide: use
Universum.id
instead. -
#170: Remove
ElementConstraint
from theContainer
class.Migration guide: remove
ElementConstraint
from every instance and every type signature. -
#174 The
type-operators
dependency has been removed. -
#177: The
mask_
reexport fromsafe-exceptions
has been deprecated.Migration_guide: use
Control.Exception.Safe.mask_
fromsafe-exceptions
instead. -
#178:
getArgs
has been deprecated. To be removed in a future version.Migration guide: use
liftIO
directly withSystem.Environment.getArgs
frombase
. -
#179:
getContents
andinteract
have been deprecated.Migration guide: use
liftIO
directly withData.Text.Lazy.IO.getContents
andData.Text.Lazy.IO.interact
, both from thetext
package. -
#180: The
Lifted.ST
module has been deprecated. To be removed in a future version.Migration guide: use
liftIO
directly with functions fromControl.Monad.ST
instead. -
#181:
list
has been deprecated. To be removed in a future version.
1.2.0
-
#159 Breaking change: Remove
text-format
dependency.Migration guide: import
Buildable
type class either fromtext-format
orformatting
orfmt
library. There is no direct replacement forpretty
andprettyL
in popular libraries. You can defineprettyL = Data.Text.Lazy.Builder.toLazyText . build
andpretty = Data.Text.Lazy.toStrict
. prettyL`. -
#164: Don’t reexport
log :: Floating a => a -> a
.
1.1.1
- #148:
Add
CODEOWNERS
and contributing guide. - #135: Add documentation regarding internal module structure.
- #113:
Annotate
at
function fromUnsafe
module andordNub
function fromNub
module withliquidhaskell
. - #73: Add more examples to docs and fix warnings where possible.
- Move reexport of
NonEmpty
toUniversum.List
module.
1.1.0
- #144:
Add
Exc
pattern synonym. - #60:
Reexport
Natural
type fromNumeric.Natura
module. - #118:
Reexport
Type
fromData.Kind
module. - #130:
Merge
ToList
andContainer
type classes into single type classContainer
. - #15:
Add
?:
function toUniversum.Monad.Maybe
. - #128:
Add
Unsafe
module with unsafe functions to works with lists andMaybe
. - #129:
Reexport
id
. - #136:
Change
foldl'
type back, addflipfoldl'
instead.
1.0.4.1
- #127:
Fix
doctest
fortext-1.2.3
.
1.0.4
- #53:
Add
doctest
touniversum
. Also imporove and fix documentation. - #117:
Drop the support of
GHC-8.0.1
. - #104:
Reexport
hashWithSalt
fromData.Hashable
. - #95:
Reexport
Compose
fromData.Functor.Compose
. - #124:
Export methods of class
Exception
.
1.0.3
- #114:
Reexport more functions from
safe-exceptions
.
1.0.2
- #91:
Change argument order of
foldl'
. - #97:
Add
ToPairs
type class with the ability to have list of pairs.
1.0.1
- #100:
Add
bug
function =impureThrow
.
1.0.0
- #90: Improve project structure.
- #89:
Add export of
Universum.Nub
module toUniversum
. - Add
listToMaybe
toUniversum.Monad.Reexport
. - #81:
Make
putText
andputLText
to be versions ofputStr
. AddputTextLn
andputLTextLn
– versions ofputStrLn
. - #5:
Add safe versions of
head
,tail
,init
,last
functions forNonEmpty
list. Oldhead
(which returnsMaybe
) is renamed tosafeHead
. Reexports fromsafe
are removed. - Remove
unsnoc
(this function is very slow and shouldn’t be used). - #88:
Add
HasCallStack =>
toerror
andundefined
functions. - #58:
Make
Element
type family be associated type family. Remove{-# OVERLAPPABLE #-}
instance forToList
andContainer
. Add default instances for basic types. RemoveWrappedList
newtype
because it’s not needed anymore. RemoveNontrivialContainer
constraint alias. - #56:
Make
elem
andnotElem
faster forSet
andHashSet
by introducingElementConstraint
associated type family. - Remove
Unsafe
module. Though, see issue #128 for disuccion regarding possible return of this module.
0.9.1
- Change
base
version to be< 5
.
0.9.0
- #79: Import ‘(<>)’ from Semigroup, not Monoid.
- Improve travis configartion.
- #80:
Rename
Container
toToList
,NontrivialContainer
toContainer
. KeepNontrivialContainer
as type alias. - Rename
Containers
module toContainer.Class
. - Move all container-related reexports from
Universum
toContainer.Reexport
. - Add default implementation of
null
function. - Add
WrappedList
newtype with instance ofContainer
. - Improve compile time error messages for disallowed instances.
0.8.0
- #83:
Change the order of types in
show
andprint
functions. - Move string related reexports and functions to
Conv
module. - Rename
Conv
module toString
. - Move
print
function toPrint
module. - #77:
Add
modify'
function to export list.
0.7.1.1
- #69:
Document
SuperComposition
operator(...)
.
0.7.1
- #68:
Separate all ‘nub’ functions to
Nub
module, addsortNub
andunstableNub
there. - #54: Reorganize .cabal.
- #21: Add benchmarks.
- #65:
Use
TypeNats
instead ofTypeLits
when possible.
0.7.0
- #47:
Reexport
put
andget
forMonadState
. - #48:
Export boxed
Vector
type. - #49:
Export
IdentityT
andrunIdentityT
. - #51:
Add
fromRight
andfromLeft
that behave likefromMaybe
but forEither
. - #52:
Add
maybeToMonoid :: Monoid m => Maybe m -> m
. - Remove
Symbol
-related types for sure. - Return back seems to be useful function
guardM
removed inv0.3
. - Add
notElem
forNonTrivialContainer
.
0.6.1
- Fixed version number bug (it had 4 numbers).
0.6.0.0
- #62: Export exceptions-related functions from ‘safe-exceptions’.
0.5.1
- Fix an infinite loop in
decodeUtf8
fromText
toByteString.Lazy
.
0.5
- Export
MonadTrans
typeclass. - Remove
Symbol
-related exports fromGHC.TypeLits
. - Remove
SrcLoc
andLocation
reexports fromGHC.ExecutionStack
. - Add
With
type operator. - Add
hashNub
. - Export strict
StateT
instead of lazy.
0.4.3
- Assign associativity and priority to (…), export typeclass itself.
0.4.2
- #25: Add vararg functions composition operator (…).
- Rewrite
concatMapM
&concatForM
so that they allow traversed and returned-by-function container types differ.
0.4.1
- Reexport
sortWith
fromGHC.Exts
.
0.4
- Add haddock documentation with 100% coverage.
- Rewrite README tutorial.
- #37:
Add generalized version of
readEither
. - #38:
Add
evaluateNF
,evaluateNF_
,evaluateWHNF
,evaluateWHNF_
. - #39:
Add lifted versions of
IORef
functions. - Remove
foreach
- Reexport
(&&&)
fromControl.Arrow
. - Add lifted version of
readTVarIO
. interact
andgetContents
work with Lazy Text.- Reexport
MaybeT
,maybeToExceptT
,exceptToMaybeT
.
0.3
- #28:
Remove
putByteString
andputLByteString
. - #29:
Remove
panic
,FatalError
andnotImplemented
. RenameNotImplemented
intoUndefined
. - #32:
Remove
orAlt
,orEmpty
,liftAA2
,eitherA
,purer
,<<*>>
,traceIO
,guardM
,hush
,tryIO
,liftM'
,liftM2'
,applyN
,guardedA
, Bifunctor instances for tuples of length higher than 2. GeneralizeconcatMapM
, addconcatForM
and operator versions. - #35:
Generalize
andM
,orM
,allM
,anyM
over container type.
0.2.2
- #33:
Add
($)
andEach
type operators.
0.2.1
- #24:
Add
whenNothing
,whenNothing_
,whenNothingM
,whenNothingM_
,whenLeft
,whenLeftM
,whenRight
,whenRightM
,whenNotNull
,whenNotNullM
. - #26:
Add
usingReader
,usingReaderT
,usingState
,usingStateT
,executingState
,executingStateT
,evaluatingState
,evaluatingStateT
. - Remove
maybeToEither
.
0.2
- Add
one
(similar tosingleton
). - Expose
Symbol
andNat
types fromGHC.TypeLits
by default. - Export
genericLength
and other generic list return functions. - Rename
msg
tofatalErrorMessage
. - Export
ExceptT
- Export
ReaderT
, andStateT
constructors. - Export
NonEmpty
type and constructor for Base 4.9 only. - Export
Data.Semigroup
type and functions for Base 4.9 only. - Export
String
.
0.1.13
- Add lenses from
microlens
. - Add
(<&>)
. - Reexport
(&)
fromData.Function
if it’s present there instead of always defining our own (this is actually done by reexporting it fromLens.Micro
which does the right thing). - Fix a space leak in
whenJust
.
0.1.12
-
Use custom classes instead of
Foldable
. Thanks to this,length
and similar functions can’t anymore be used on tuples orMaybe
, but can be used on e.g.Text
,ByteString
andIntSet
. -
Add
allM
,anyM,
andM
,orM
. -
Reexport
fail
andMonadFail
.
0.1.11
- Expose
putByteString
andputLByteString
monomorphic versions ofputStrLn
functions - Switch exported
(<>)
to be fromData.Monoid
instead of Semigroup. - Export
Hashable
0.1.10
- Generalize most
IO
functions toMonadIO
- Make
die
available for older versions of base
0.1.9
- Make
sum
andproduct
strict
0.1.8
foreach
for applicative traversals.hush
function for error handling.tryIO
function for error handling.pass
function for noop applicative branches.- Mask
Handler
typeclass export. - Mask
yield
function export.
0.1.7
- Export monadic
(>>)
operator by default. - Add
traceId
andtraceShowId
functions. - Export
reader
andstate
functions by default. - Export lifted
throwIO
andthrowTo
functions.
0.1.6
- Add uncatchable panic exception throwing using Text message.
- Remove
printf
- Remove
string-conv
dependency so Stack build works withoutextra-deps
. - Bring
Callstack
machinery in for GHC 8.x. - Remove
throw
andassert
fromControl.Exception
exports. - Remove
unsafeShiftL
andunsafeShiftR
fromData.Bits
exports. - Reexport
throw
asunsafeThrow
via Unsafe module. - Hides all Show class functions. Only the Class itself is exported. Forbids custom instances that are not GHC derived.
- Export
encodeUtf8
anddecodeUtf8
functions by default. - Adds
unsnoc
function.
0.1.5
- Initial release.