streamly-core-0.2.1: Streaming, parsers, arrays, serialization and more
Copyright(c) 2021 Composewell Technologies
LicenseBSD-3-Clause
Maintainerstreamly@composewell.com
Stabilityreleased
PortabilityGHC
Safe HaskellSafe-Inferred
LanguageHaskell2010

Streamly.Unicode.Parser

Description

To parse a text input, use the decode routines from Streamly.Unicode.Stream module to convert an input byte stream to a Unicode Char stream and then use these parsers on the Char stream.

Synopsis

Setup

To execute the code examples provided in this module in ghci, please run the following commands first.

>>> :m
>>> import qualified Streamly.Data.Stream as Stream
>>> import qualified Streamly.Unicode.Parser as Unicode

For APIs that have not been released yet.

>>> import qualified Streamly.Internal.Unicode.Parser as Unicode (number, mkDouble)

Single Chars

char :: Monad m => Char -> Parser Char m Char Source #

Match a specific character.

charIgnoreCase :: Monad m => Char -> Parser Char m Char Source #

Match a specific character ignoring case.

alpha :: Monad m => Parser Char m Char Source #

Match any character that satisfies isAlpha

alphaNum :: Monad m => Parser Char m Char Source #

Match any character that satisfies isAlphaNum

letter :: Monad m => Parser Char m Char Source #

Match any character that satisfies isLetter

ascii :: Monad m => Parser Char m Char Source #

Match any character that satisfies isAscii

asciiLower :: Monad m => Parser Char m Char Source #

Match any character that satisfies isAsciiLower

asciiUpper :: Monad m => Parser Char m Char Source #

Match any character that satisfies isAsciiUpper

latin1 :: Monad m => Parser Char m Char Source #

Match any character that satisfies isLatin1

lower :: Monad m => Parser Char m Char Source #

Match any character that satisfies isLower

upper :: Monad m => Parser Char m Char Source #

Match any character that satisfies isUpper

mark :: Monad m => Parser Char m Char Source #

Match any character that satisfies isMark

printable :: Monad m => Parser Char m Char Source #

Match any character that satisfies isPrint

punctuation :: Monad m => Parser Char m Char Source #

Match any character that satisfies isPunctuation

separator :: Monad m => Parser Char m Char Source #

Match any character that satisfies isSeparator

space :: Monad m => Parser Char m Char Source #

Match any character that satisfies isSpace

symbol :: Monad m => Parser Char m Char Source #

Match any character that satisfies isSymbol

digit :: Monad m => Parser Char m Char Source #

Match any character that satisfies isDigit

octDigit :: Monad m => Parser Char m Char Source #

Match any character that satisfies isOctDigit

hexDigit :: Monad m => Parser Char m Char Source #

Match any character that satisfies isHexDigit

numeric :: Monad m => Parser Char m Char Source #

Match any character that satisfies isNumber

Char Sequences

string :: Monad m => String -> Parser Char m String Source #

Match the input with the supplied string and return it if successful.

stringIgnoreCase :: Monad m => String -> Parser Char m String Source #

Match the input with the supplied string and return it if successful.

dropSpace :: Monad m => Parser Char m () Source #

Drop zero or more white space characters.

dropSpace1 :: Monad m => Parser Char m () Source #

Drop one or more white space characters.

Digit Sequences (Numbers)

decimal :: (Monad m, Integral a) => Parser Char m a Source #

Parse and decode an unsigned integral decimal number.

hexadecimal :: (Monad m, Integral a, Bits a) => Parser Char m a Source #

Parse and decode an unsigned integral hexadecimal number. The hex digits 'a' through 'f' may be upper or lower case.

Note: This parser does not accept a leading "0x" string.

double :: Monad m => Parser Char m Double Source #

Parse a decimal Double value. This parser accepts an optional sign (+ or -) followed by at least one decimal digit. Decimal digits are optionally followed by a decimal point and at least one decimal digit after the point. This parser accepts the maximal valid input as long as it gives a valid number. Specifcally a trailing decimal point is allowed but not consumed. This function does not accept "NaN" or "Infinity" string representations of double values.

Definition:

>>> double = uncurry Unicode.mkDouble <$> Unicode.number

Examples:

>>> p = Stream.parse Unicode.double . Stream.fromList
>>> p "-1.23e-123"
Right (-1.23e-123)

Trailing input examples:

>>> p "1."
Right 1.0
>>> p "1.2.3"
Right 1.2
>>> p "1e"
Right 1.0
>>> p "1e2.3"
Right 100.0
>>> p "1+2"
Right 1.0

Error cases:

>>> p ""
Left (ParseError "number: expecting sign or decimal digit, got end of input")
>>> p ".1"
Left (ParseError "number: expecting sign or decimal digit, got '.'")
>>> p "+"
Left (ParseError "number: expecting decimal digit, got end of input")

Modifiers

signed :: (Num a, Monad m) => Parser Char m a -> Parser Char m a Source #

Allow an optional leading '+' or '-' sign character before any parser.