ASCII.Char

The Char type has 128 nullary constructors, listed in order according to each character's 7-bit numeric code.

The Char type

data Char

A character in the ASCII character set

Constructors

Null

StartOfHeading

StartOfText

EndOfText

EndOfTransmission

Enquiry

Acknowledgement

Bell

Backspace

HorizontalTab

LineFeed

VerticalTab

FormFeed

CarriageReturn

ShiftOut

ShiftIn

DataLinkEscape

DeviceControl1

DeviceControl2

DeviceControl3

DeviceControl4

NegativeAcknowledgement

SynchronousIdle

EndOfTransmissionBlock

Cancel

EndOfMedium

Substitute

Escape

FileSeparator

GroupSeparator

RecordSeparator

UnitSeparator

Space

ExclamationMark

!

QuotationMark

"

NumberSign

#

DollarSign

$

PercentSign

%

Ampersand

&

Apostrophe

#

LeftParenthesis

(

RightParenthesis

)

Asterisk

*

PlusSign

+

Comma

,

HyphenMinus

-

FullStop

.

Slash

/

Digit0

Digit1

Digit2

Digit3

Digit4

Digit5

Digit6

Digit7

Digit8

Digit9

Colon

:

Semicolon

;

LessThanSign

<

EqualsSign

=

GreaterThanSign

>

QuestionMark

?

AtSign

@

CapitalLetterA

CapitalLetterB

CapitalLetterC

CapitalLetterD

CapitalLetterE

CapitalLetterF

CapitalLetterG

CapitalLetterH

CapitalLetterI

CapitalLetterJ

CapitalLetterK

CapitalLetterL

CapitalLetterM

CapitalLetterN

CapitalLetterO

CapitalLetterP

CapitalLetterQ

CapitalLetterR

CapitalLetterS

CapitalLetterT

CapitalLetterU

CapitalLetterV

CapitalLetterW

CapitalLetterX

CapitalLetterY

CapitalLetterZ

LeftSquareBracket

[

Backslash

\

RightSquareBracket

]

Caret

^

Underscore

_

GraveAccent

`

SmallLetterA

SmallLetterB

SmallLetterC

SmallLetterD

SmallLetterE

SmallLetterF

SmallLetterG

SmallLetterH

SmallLetterI

SmallLetterJ

SmallLetterK

SmallLetterL

SmallLetterM

SmallLetterN

SmallLetterO

SmallLetterP

SmallLetterQ

SmallLetterR

SmallLetterS

SmallLetterT

SmallLetterU

SmallLetterV

SmallLetterW

SmallLetterX

SmallLetterY

SmallLetterZ

LeftCurlyBracket

{

VerticalLine

|

RightCurlyBracket

}

Tilde

~

Delete

Instances

Data Char

The Data instance allows ASCII characters to be used with generic programming in the “SYB” style. (See the syb package and the 2003 paper Scrap Your Boilerplate by Ralf Lämmel and Simon Peyton Jones.)

Defined in ASCII.Char

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Char -> c Char

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Char

toConstr :: Char -> Constr

dataTypeOf :: Char -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Char)

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Char)

gmapT :: (forall b. Data b => b -> b) -> Char -> Char

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r

gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Char -> r

gmapQ :: (forall d. Data d => d -> u) -> Char -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> Char -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Char -> m Char

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Char -> m Char

Bounded Char

The least character is Null, and the greatest character is Delete. You can write ([minBound .. maxBound] :: [ASCII.Char]) to get a list of all the ASCII characters.

Defined in ASCII.Char

Methods

minBound :: Char

maxBound :: Char

Enum Char

The Enum instance allows us to use range syntax, for example [SmallLetterA .. SmallLetterZ] is a list all lower-case letters from a to z. Instead of toEnum and fromEnum, consider using toInt and fromIntMaybe.

Defined in ASCII.Char

Methods

succ :: Char -> Char

pred :: Char -> Char

toEnum :: Int -> Char

fromEnum :: Char -> Int

enumFrom :: Char -> [Char]

enumFromThen :: Char -> Char -> [Char]

enumFromTo :: Char -> Char -> [Char]

enumFromThenTo :: Char -> Char -> Char -> [Char]

Generic Char

Defined in ASCII.Char

Associated Types

type Rep Char :: Type -> Type

Methods

from :: Char -> Rep Char x

to :: Rep Char x -> Char

Show Char

show produces the name of a constructor. For example, the character e is shown as “SmallLetterE”. See ASCII.Char for the complete list of constructor names.

Defined in ASCII.Char

Methods

showsPrec :: Int -> Char -> ShowS

show :: Char -> String

showList :: [Char] -> ShowS

Eq Char

ASCII characters can be compared for equality using (==). Comparisons are case-sensitive; SmallLetterA /= CapitalLetterA.

Defined in ASCII.Char

Methods

(==) :: Char -> Char -> Bool

(/=) :: Char -> Char -> Bool

Ord Char

ASCII characters are ordered; for example, the letter A is "less than" (<) the letter B because it appears earlier in the list. The ordering of ASCII characters is the same as the ordering of the corresponding Unicode Chars.

Defined in ASCII.Char

Methods

compare :: Char -> Char -> Ordering

(<) :: Char -> Char -> Bool

(<=) :: Char -> Char -> Bool

(>) :: Char -> Char -> Bool

(>=) :: Char -> Char -> Bool

max :: Char -> Char -> Char

min :: Char -> Char -> Char

Hashable Char

The Hashable instance lets us collect ASCII characters in hash-based sets, and it lets us use ASCII characters as keys in hash-based maps. (See the unordered-containers package.)

Defined in ASCII.Char

Methods

hashWithSalt :: Int -> Char -> Int

hash :: Char -> Int

type Rep Char

The Generic instance allows ASCII characters to be used with generic programming in the “generic deriving” style. (See the generic-data package and the 2010 paper A generic deriving mechanism for Haskell by José Pedro Magalhães, Atze Dijkstra, Johan Jeuring, and Andres Löh.)

Defined in ASCII.Char

type Rep Char = D1 ('MetaData "Char" "ASCII.Char" "ascii-char-1.0.1.0-LiVxY0eZCce7UgRuMTOed" 'False) (((((((C1 ('MetaCons "Null" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "StartOfHeading" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "StartOfText" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "EndOfText" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "EndOfTransmission" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Enquiry" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Acknowledgement" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Bell" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "Backspace" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "HorizontalTab" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "LineFeed" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "VerticalTab" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "FormFeed" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CarriageReturn" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "ShiftOut" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "ShiftIn" 'PrefixI 'False) (U1 :: Type -> Type))))) :+: ((((C1 ('MetaCons "DataLinkEscape" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "DeviceControl1" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "DeviceControl2" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "DeviceControl3" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "DeviceControl4" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "NegativeAcknowledgement" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SynchronousIdle" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "EndOfTransmissionBlock" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "Cancel" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "EndOfMedium" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Substitute" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Escape" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "FileSeparator" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "GroupSeparator" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "RecordSeparator" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "UnitSeparator" 'PrefixI 'False) (U1 :: Type -> Type)))))) :+: (((((C1 ('MetaCons "Space" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "ExclamationMark" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "QuotationMark" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "NumberSign" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "DollarSign" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "PercentSign" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Ampersand" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Apostrophe" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "LeftParenthesis" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "RightParenthesis" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Asterisk" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "PlusSign" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "Comma" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "HyphenMinus" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "FullStop" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Slash" 'PrefixI 'False) (U1 :: Type -> Type))))) :+: ((((C1 ('MetaCons "Digit0" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Digit1" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Digit2" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Digit3" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "Digit4" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Digit5" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Digit6" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Digit7" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "Digit8" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Digit9" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Colon" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Semicolon" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "LessThanSign" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "EqualsSign" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "GreaterThanSign" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "QuestionMark" 'PrefixI 'False) (U1 :: Type -> Type))))))) :+: ((((((C1 ('MetaCons "AtSign" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterA" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CapitalLetterB" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterC" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "CapitalLetterD" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterE" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CapitalLetterF" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterG" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "CapitalLetterH" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterI" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CapitalLetterJ" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterK" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "CapitalLetterL" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterM" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CapitalLetterN" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterO" 'PrefixI 'False) (U1 :: Type -> Type))))) :+: ((((C1 ('MetaCons "CapitalLetterP" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterQ" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CapitalLetterR" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterS" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "CapitalLetterT" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterU" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CapitalLetterV" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterW" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "CapitalLetterX" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "CapitalLetterY" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CapitalLetterZ" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "LeftSquareBracket" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "Backslash" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "RightSquareBracket" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Caret" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Underscore" 'PrefixI 'False) (U1 :: Type -> Type)))))) :+: (((((C1 ('MetaCons "GraveAccent" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterA" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SmallLetterB" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterC" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "SmallLetterD" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterE" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SmallLetterF" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterG" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "SmallLetterH" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterI" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SmallLetterJ" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterK" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "SmallLetterL" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterM" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SmallLetterN" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterO" 'PrefixI 'False) (U1 :: Type -> Type))))) :+: ((((C1 ('MetaCons "SmallLetterP" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterQ" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SmallLetterR" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterS" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "SmallLetterT" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterU" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SmallLetterV" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterW" 'PrefixI 'False) (U1 :: Type -> Type)))) :+: (((C1 ('MetaCons "SmallLetterX" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "SmallLetterY" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "SmallLetterZ" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "LeftCurlyBracket" 'PrefixI 'False) (U1 :: Type -> Type))) :+: ((C1 ('MetaCons "VerticalLine" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "RightCurlyBracket" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "Tilde" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Delete" 'PrefixI 'False) (U1 :: Type -> Type))))))))

Int

toInt :: Char -> Int

Converts an ASCII character to its corresponding numeric value between 0 and 127

toInt Null == 0
toInt CapitalLetterA == 6
toInt SmallLetterA == 97
toInt Delete == 127

fromIntMaybe :: Int -> Maybe Char

Returns Just the ASCII character corresponding to a numeric value between 0 and 127, or Nothing for numbers outside this range

fromIntMaybe (-1) == Nothing
fromIntMaybe 0 == Just Null
fromIntMaybe 65 == Just CapitalLetterA
fromIntMaybe 127 == Just Delete
fromIntMaybe 128 == Nothing

fromIntUnsafe :: Int -> Char

The inverse of toInt

This is marked as unsafe because it is undefined for numbers below 0 or above 127. The safe variant of this function is fromIntMaybe.

fromIntUnsafe (-1) == undefined
fromIntUnsafe 65 == CapitalLetterA
fromIntUnsafe 66 == CapitalLetterB
fromIntUnsafe 67 == CapitalLetterC
fromIntUnsafe 128 == undefined

Word8

toWord8 :: Char -> Word8

Converts an ASCII character to its corresponding byte between 0 and 127

toWord8 Null == 0
toWord8 CapitalLetterA == 6
toWord8 SmallLetterA == 97
toWord8 Delete == 127

fromWord8Maybe :: Word8 -> Maybe Char

Returns Just the ASCII character corresponding to a byte between 0 and 127, or Nothing for bytes above this range

fromWord8Maybe 0 == Just Null
fromWord8Maybe 65 == Just CapitalLetterA
fromWord8Maybe 127 == Just Delete
fromWord8Maybe 128 == Nothing

fromWord8Unsafe :: Word8 -> Char

The inverse of toWord8

This is marked as unsafe because it is undefined bytes above 127. The safe variant of this function is fromWord8Maybe.

fromWord8Unsafe 65 == CapitalLetterA
fromWord8Unsafe 66 == CapitalLetterB
fromWord8Unsafe 67 == CapitalLetterC
fromWord8Unsafe 128 == undefined

Enumeration

allCharacters :: [Char]

Notes

There are 128 characters in total.

length allCharacters == 128

Null is the first character.

minBound == Null

Delete is the last character.

maxBound == Delete