Haskell modules in TypeScript

TypeScript implementations of 10 Haskell standard library functions across 1 module. Each function is individually importable and tree-shakeable.

list

We have 10 Haskell functions so far - help us add more

Got a rainy Sunday afternoon and a taste for a porting puzzle?

Get inspiration from the Haskell base Data.List docs.
Click "New file" in the appropriate folder on GitHub. This will fork the project to your account, directly add the file to it, and send a Pull Request to us.

We will then review it. If it's useful to the project and in line with our contributing guidelines your work will become part of Locutus and you'll be automatically credited in the authors section accordingly.

Upstream Surface Inventory 10/3210 shipped · 213 next 0%

Locutus tracks 131 upstream namespaces for Haskell and sorts them into what is already shipped, what we still want, what we intentionally keep, and what still needs a decision.

This inventory now tracks a broader official `base` module slice for Haskell's core plain-value helpers, not the wider Hackage ecosystem.

0% catalog shipped

Shipped Next Explicit non-goals

Data.List 9% Numeric 0% Data.Char 0% Data.Ord 0% Data.Tuple 0% Data.Maybe 0% Data.Bool 0% Data.Either 0% Data.Function 0% Numeric.Natural 0% Control.Applicative 0% Control.Arrow 0% Control.Category 0% Control.Concurrent 0% Control.Concurrent.Chan 0% Control.Concurrent.MVar 0% Control.Concurrent.QSem 0% Control.Concurrent.QSemN 0% Control.Exception 0% Control.Exception.Annotation 0% Control.Exception.Backtrace 0% Control.Exception.Base 0% Control.Exception.Context 0% Control.Monad 0% Control.Monad.Fail 0% Control.Monad.Fix 0% Control.Monad.Instances 0% Control.Monad.IO.Class 0% Control.Monad.ST 0% Control.Monad.ST.Lazy 0% Control.Monad.ST.Lazy.Safe 0% Control.Monad.ST.Lazy.Unsafe 0% Control.Monad.ST.Safe 0% Control.Monad.ST.Strict 0% Control.Monad.ST.Unsafe 0% Control.Monad.Zip 0% Data.Array.Byte 0% Data.Bifoldable 0% Data.Bifoldable1 0% Data.Bifunctor 0% Data.Bitraversable 0% Data.Bits 0% Data.Coerce 0% Data.Complex 0% Data.Data 0% Data.Dynamic 0% Data.Enum 0% Data.Eq 0% Data.Fixed 0% Data.Foldable 0% Data.Foldable1 0% Data.Functor 0% Data.Functor.Classes 0% Data.Functor.Compose 0% Data.Functor.Const 0% Data.Functor.Contravariant 0% Data.Functor.Identity 0% Data.Functor.Product 0% Data.Functor.Sum 0% Data.Int 0% Data.IORef 0% Data.Ix 0% Data.Kind 0% Data.List.NonEmpty 0% Data.Monoid 0% Data.Proxy 0% Data.Ratio 0% Data.Semigroup 0% Data.STRef 0% Data.STRef.Lazy 0% Data.STRef.Strict 0% Data.String 0% Data.Traversable 0% Data.Type.Bool 0% Data.Type.Coercion 0% Data.Type.Equality 0% Data.Type.Ord 0% Data.Typeable 0% Data.Unique 0% Data.Version 0% Data.Void 0% Data.Word 0% Debug.Trace 0% Foreign 0% Foreign.C 0% Foreign.C.ConstPtr 0% Foreign.C.Error 0% Foreign.C.String 0% Foreign.C.Types 0% Foreign.Concurrent 0% Foreign.ForeignPtr 0% Foreign.ForeignPtr.Safe 0% Foreign.ForeignPtr.Unsafe 0% Foreign.Marshal 0% Foreign.Marshal.Alloc 0% Foreign.Marshal.Array 0% Foreign.Marshal.Error 0% Foreign.Marshal.Pool 0% Foreign.Marshal.Safe 0% Foreign.Marshal.Unsafe 0% Foreign.Marshal.Utils 0% Foreign.Ptr 0% Foreign.Safe 0% Foreign.StablePtr 0% Foreign.Storable 0% Prelude 0% System.Console.GetOpt 0% System.CPUTime 0% System.Environment 0% System.Environment.Blank 0% System.Exit 0% System.Info 0% System.IO 0% System.IO.Error 0% System.IO.Unsafe 0% System.Mem 0% System.Mem.StableName 0% System.Mem.Weak 0% System.Posix.Internals 0% System.Posix.Types 0% System.Timeout 0% Text.ParserCombinators.ReadP 0% Text.ParserCombinators.ReadPrec 0% Text.Printf 0% Text.Read 0% Text.Read.Lex 0% Text.Show 0% Text.Show.Functions 0% Type.Reflection 0% Type.Reflection.Unsafe 0% Unsafe.Coerce 0%

Tracked namespaces 131

Shipped 10/3210

Next to port 213

Explicit non-goals 2987

In progress

10/109 shipped 99 next

list

Shipped (10)

Pure list transforms and combinatorics helpers are strong plain-value portability targets.

all
and
any
break
concat
concatMap
cycle
delete
deleteBy
deleteFirstsBy
drop
dropWhile
dropWhileEnd
elem
elemIndex
elemIndices
filter
find
findIndex
findIndices
Foldable
foldl
foldl'
foldr
genericDrop
genericIndex
genericLength
genericReplicate
genericSplitAt
genericTake
init
insert
insertBy
intersect
intersectBy
isInfixOf
isPrefixOf
isSubsequenceOf
isSuffixOf
iterate
iterate'
length
lines
List
lookup
map
mapAccumL
mapAccumR
notElem
nub
null
or
partition
product
repeat
replicate
reverse
scanl
scanl'
scanl1
scanr
scanr1
singleton
sort
sortBy
sortOn
span
splitAt
stripPrefix
sum
tail
take
takeWhile
Traversable
uncons
unfoldr
union
unionBy
unlines
unsnoc
unwords
unzip3
unzip4
unzip5
unzip6
unzip7
words
zip
zip3
zip4
zip5
zip6
zip7
zipWith
zipWith3
zipWith4
zipWith5
zipWith6
zipWith7

0/44 shipped 44 next 2 explicit non-goals

Base-conversion and numeric-format helpers are strong portability targets.

acos
acosh
asin
asinh
atan
atanh
cos
cosh
exp
expm1
floatToDigits
fromRat
lexDigits
log
log1mexp
log1p
log1pexp
logBase
pi
readBin
readDec
readFloat
readHex
readInt
readOct
readSigned
showBin
showEFloat
showFFloat
showFFloatAlt
showFloat
showGFloat
showGFloatAlt
showHex
showHFloat
showInt
showIntAtBase
showOct
showSigned
sin
sinh
sqrt
tan
tanh

Explicit non-goals (2)

class Skip Typeclass and declaration exports are runtime/model declarations rather than direct plain-value helpers.
Floating Skip Typeclass and declaration exports are runtime/model declarations rather than direct plain-value helpers.

0/33 shipped 33 next 32 explicit non-goals

Character classification and case helpers are strong Haskell plain-value portability targets.

chr
digitToInt
generalCategory
intToDigit
isAlpha
isAlphaNum
isAscii
isAsciiLower
isAsciiUpper
isControl
isDigit
isHexDigit
isLatin1
isLetter
isLower
isLowerCase
isMark
isNumber
isOctDigit
isPrint
isPunctuation
isSeparator
isSpace
isSymbol
isUpper
isUpperCase
lexLitChar
ord
readLitChar
showLitChar
toLower
toTitle
toUpper

Explicit non-goals (32)

Char Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
ClosePunctuation Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
ConnectorPunctuation Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
Control Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
CurrencySymbol Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
DashPunctuation Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
DecimalNumber Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
EnclosingMark Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
FinalQuote Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
Format Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
GeneralCategory Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
InitialQuote Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
LetterNumber Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
LineSeparator Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
LowercaseLetter Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
MathSymbol Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
ModifierLetter Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
ModifierSymbol Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
NonSpacingMark Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
NotAssigned Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
OpenPunctuation Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
OtherLetter Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
OtherNumber Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
OtherPunctuation Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
OtherSymbol Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
ParagraphSeparator Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
PrivateUse Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
Space Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
SpacingCombiningMark Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
Surrogate Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
TitlecaseLetter Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.
UppercaseLetter Skip Type and category exports are runtime/model declarations rather than direct plain-value helpers.

0/14 shipped 14 next

Ordering helpers over plain values are strong Haskell portability targets.

clamp
class
compare
comparing
Down
EQ
getDown
GT
LT
max
min
newtype
Ord
Ordering

0/9 shipped 9 next

Tuple projection and transformation helpers map cleanly to plain arrays.

curry
fst
getSolo
MkSolo
pattern
snd
Solo
swap
uncurry

0/6 shipped 6 next 6 explicit non-goals

Null-filtering helpers have a clean plain-value contract.

catMaybes

Defaulting helpers have a clean plain-value contract.

fromMaybe

Optional-value predicates have a clean plain-value contract.

isJust
isNothing

Combined map-filter helpers are strong plain-value targets.

mapMaybe

Optional branching over plain values has a clean contract.

maybe

Explicit non-goals (6)

fromJust Skip Maybe wrappers do not map directly to one stable plain-value contract.
Just Skip Maybe wrappers do not map directly to one stable plain-value contract.
listToMaybe Skip Maybe wrappers do not map directly to one stable plain-value contract.
Maybe Skip Maybe wrappers do not map directly to one stable plain-value contract.
maybeToList Skip Maybe wrappers do not map directly to one stable plain-value contract.
Nothing Skip Maybe wrappers do not map directly to one stable plain-value contract.

0/3 shipped 3 next 3 explicit non-goals

Boolean branching helpers have a clean plain-value contract.

bool
not
otherwise

Explicit non-goals (3)

Bool Skip Type and constructor exports are runtime/model declarations rather than direct plain-value helpers.
False Skip Type and constructor exports are runtime/model declarations rather than direct plain-value helpers.
True Skip Type and constructor exports are runtime/model declarations rather than direct plain-value helpers.

0/3 shipped 3 next 8 explicit non-goals

Branching over plain values still has a useful portability contract.

either

Sum-type predicates have a clean plain-value contract.

isLeft
isRight

Explicit non-goals (8)

Either Skip Sum-type wrappers do not map directly to one stable plain-value contract.
fromLeft Skip Sum-type wrappers do not map directly to one stable plain-value contract.
fromRight Skip Sum-type wrappers do not map directly to one stable plain-value contract.
Left Skip Sum-type wrappers do not map directly to one stable plain-value contract.
lefts Skip Sum-type wrappers do not map directly to one stable plain-value contract.
partitionEithers Skip Sum-type wrappers do not map directly to one stable plain-value contract.
Right Skip Sum-type wrappers do not map directly to one stable plain-value contract.
rights Skip Sum-type wrappers do not map directly to one stable plain-value contract.

0/1 shipped 1 next 4 explicit non-goals

Comparator and projection composition still has a useful plain-value portability contract.

on

Explicit non-goals (4)

applyWhen Skip Higher-order function combinators are less compelling than direct JS equivalents by default.
const Skip Higher-order function combinators are less compelling than direct JS equivalents by default.
fix Skip Higher-order function combinators are less compelling than direct JS equivalents by default.
flip Skip Higher-order function combinators are less compelling than direct JS equivalents by default.

0/1 shipped 1 next 1 explicit non-goals

Numeric helper modules are strong scalar and formatting portability targets.

minusNaturalMaybe

Explicit non-goals (1)

Natural Skip Type exports are runtime/model declarations rather than direct plain-value helpers.

Triaged as out of scope

Control.Applicative Haskell 9.10 base

0/0 24 skipped

Control.Arrow Haskell 9.10 base

0/0 24 skipped

Control.Category Haskell 9.10 base

0/0 4 skipped

Control.Concurrent Haskell 9.10 base

0/0 62 skipped

Control.Concurrent.Chan Haskell 9.10 base

0/0 7 skipped

Control.Concurrent.MVar Haskell 9.10 base

0/0 19 skipped

Control.Concurrent.QSem Haskell 9.10 base

0/0 5 skipped

Control.Concurrent.QSemN Haskell 9.10 base

0/0 4 skipped

Control.Exception Haskell 9.10 base

0/0 82 skipped

Control.Exception.Annotation Haskell 9.10 base

0/0 5 skipped

Control.Exception.Backtrace Haskell 9.10 base

0/0 10 skipped

Control.Exception.Base Haskell 9.10 base

0/0 86 skipped

Control.Exception.Context Haskell 9.10 base

0/0 7 skipped

Control.Monad Haskell 9.10 base

0/0 39 skipped

Control.Monad.Fail Haskell 9.10 base

0/0 3 skipped

Control.Monad.Fix Haskell 9.10 base

0/0 4 skipped

Control.Monad.Instances Haskell 9.10 base

0/0 5 skipped

Control.Monad.IO.Class Haskell 9.10 base

0/0 3 skipped

Control.Monad.ST Haskell 9.10 base

0/0 7 skipped

Control.Monad.ST.Lazy Haskell 9.10 base

0/0 5 skipped

Control.Monad.ST.Lazy.Safe Haskell 9.10 base

0/0 5 skipped

Control.Monad.ST.Lazy.Unsafe Haskell 9.10 base

0/0 2 skipped

Control.Monad.ST.Safe Haskell 9.10 base

0/0 3 skipped

Control.Monad.ST.Strict Haskell 9.10 base

0/0 3 skipped

Control.Monad.ST.Unsafe Haskell 9.10 base

0/0 3 skipped

Control.Monad.Zip Haskell 9.10 base

0/0 5 skipped

Data.Array.Byte Haskell 9.10 base

0/0 3 skipped

Data.Bifoldable Haskell 9.10 base

0/0 39 skipped

Data.Bifoldable1 Haskell 9.10 base

0/0 4 skipped

Data.Bifunctor Haskell 9.10 base

0/0 3 skipped

Data.Bitraversable Haskell 9.10 base

0/0 13 skipped

Data.Bits Haskell 9.10 base

0/0 40 skipped

Data.Coerce Haskell 9.10 base

0/0 4 skipped

Data.Complex Haskell 9.10 base

0/0 9 skipped

Data.Data Haskell 9.10 base

0/0 106 skipped

Data.Dynamic Haskell 9.10 base

0/0 9 skipped

Data.Enum Haskell 9.10 base

0/0 13 skipped

Data.Eq Haskell 9.10 base

0/0 2 skipped

Data.Fixed Haskell 9.10 base

0/0 26 skipped

Data.Foldable Haskell 9.10 base

0/0 39 skipped

Data.Foldable1 Haskell 9.10 base

0/0 17 skipped

Data.Functor Haskell 9.10 base

0/0 4 skipped

Data.Functor.Classes Haskell 9.10 base

0/0 54 skipped

Data.Functor.Compose Haskell 9.10 base

0/0 6 skipped

Data.Functor.Const Haskell 9.10 base

0/0 4 skipped

Data.Functor.Contravariant Haskell 9.10 base

0/0 16 skipped

Data.Functor.Identity Haskell 9.10 base

0/0 3 skipped

Data.Functor.Product Haskell 9.10 base

0/0 5 skipped

Data.Functor.Sum Haskell 9.10 base

0/0 5 skipped

Data.Int Haskell 9.10 base

0/0 5 skipped

Data.IORef Haskell 9.10 base

0/0 11 skipped

Data.Ix Haskell 9.10 base

0/0 6 skipped

Data.Kind Haskell 9.10 base

0/0 4 skipped

Data.List.NonEmpty Haskell 9.10 base

0/0 22 skipped

Data.Monoid Haskell 9.10 base

0/0 27 skipped

Data.Proxy Haskell 9.10 base

0/0 4 skipped

Data.Ratio Haskell 9.10 base

0/0 5 skipped

Data.Semigroup Haskell 9.10 base

0/0 33 skipped

Data.STRef Haskell 9.10 base

0/0 7 skipped

Data.STRef.Lazy Haskell 9.10 base

0/0 3 skipped

Data.STRef.Strict Haskell 9.10 base

0/0 3 skipped

Data.String Haskell 9.10 base

0/0 8 skipped

Data.Traversable Haskell 9.10 base

0/0 15 skipped

Data.Type.Bool Haskell 9.10 base

0/0 3 skipped

Data.Type.Coercion Haskell 9.10 base

0/0 11 skipped

Data.Type.Equality Haskell 9.10 base

0/0 14 skipped

Data.Type.Ord Haskell 9.10 base

0/0 9 skipped

Data.Typeable Haskell 9.10 base

0/0 44 skipped

Data.Unique Haskell 9.10 base

0/0 4 skipped

Data.Version Haskell 9.10 base

0/0 6 skipped

Data.Void Haskell 9.10 base

0/0 3 skipped

Data.Word Haskell 9.10 base

0/0 12 skipped

Debug.Trace Haskell 9.10 base

0/0 17 skipped

Foreign Haskell 9.10 base

0/0 171 skipped

Foreign.C Haskell 9.10 base

0/0 187 skipped

Foreign.C.ConstPtr Haskell 9.10 base

0/0 4 skipped

Foreign.C.Error Haskell 9.10 base

0/0 129 skipped

Foreign.C.String Haskell 9.10 base

0/0 29 skipped

Foreign.C.Types Haskell 9.10 base

0/0 30 skipped

Foreign.Concurrent Haskell 9.10 base

0/0 2 skipped

Foreign.ForeignPtr Haskell 9.10 base

0/0 16 skipped

Foreign.ForeignPtr.Safe Haskell 9.10 base

0/0 15 skipped

Foreign.ForeignPtr.Unsafe Haskell 9.10 base

0/0 1 skipped

Foreign.Marshal Haskell 9.10 base

0/0 66 skipped

Foreign.Marshal.Alloc Haskell 9.10 base

0/0 11 skipped

Foreign.Marshal.Array Haskell 9.10 base

0/0 23 skipped

Foreign.Marshal.Error Haskell 9.10 base

0/0 5 skipped

Foreign.Marshal.Pool Haskell 9.10 base

0/0 17 skipped

Foreign.Marshal.Safe Haskell 9.10 base

0/0 66 skipped

Foreign.Marshal.Unsafe Haskell 9.10 base

0/0 1 skipped

Foreign.Marshal.Utils Haskell 9.10 base

0/0 11 skipped

Foreign.Ptr Haskell 9.10 base

0/0 20 skipped

Foreign.Safe Haskell 9.10 base

0/0 169 skipped

Foreign.StablePtr Haskell 9.10 base

0/0 6 skipped

Foreign.Storable Haskell 9.10 base

0/0 10 skipped

Prelude Haskell 9.10 base

0/0 201 skipped

System.Console.GetOpt Haskell 9.10 base

0/0 13 skipped

System.CPUTime Haskell 9.10 base

0/0 2 skipped

System.Environment Haskell 9.10 base

0/0 11 skipped

System.Environment.Blank Haskell 9.10 base

0/0 8 skipped

System.Exit Haskell 9.10 base

0/0 7 skipped

System.Info Haskell 9.10 base

0/0 5 skipped

System.IO Haskell 9.10 base

0/0 109 skipped

System.IO.Error Haskell 9.10 base

0/0 46 skipped

System.IO.Unsafe Haskell 9.10 base

0/0 4 skipped

System.Mem Haskell 9.10 base

0/0 8 skipped

System.Mem.StableName Haskell 9.10 base

0/0 5 skipped

System.Mem.Weak Haskell 9.10 base

0/0 11 skipped

System.Posix.Internals Haskell 9.10 base

0/0 129 skipped

System.Posix.Types Haskell 9.10 base

0/0 38 skipped

System.Timeout Haskell 9.10 base

0/0 3 skipped

Text.ParserCombinators.ReadP Haskell 9.10 base

0/0 32 skipped

Text.ParserCombinators.ReadPrec Haskell 9.10 base

0/0 12 skipped

Text.Printf Haskell 9.10 base

0/0 43 skipped

Text.Read Haskell 9.10 base

0/0 37 skipped

Text.Read.Lex Haskell 9.10 base

0/0 22 skipped

Text.Show Haskell 9.10 base

0/0 11 skipped

Type.Reflection Haskell 9.10 base

0/0 27 skipped

Type.Reflection.Unsafe Haskell 9.10 base

0/0 24 skipped

Unsafe.Coerce Haskell 9.10 base

0/0 8 skipped

Not yet triaged

Text.Show.Functions Haskell 9.10 base

0/0