Data.ByteString.Read

Documentation

class Source a

Minimal complete definition

null, empty, head, tail

Instances

Source ByteString

Source ByteString

fractional

class (Fractional a, Num (Fraction a), Ord (Fraction a)) => ReadFractional a

Minimal complete definition

maxValue, fromFraction

Instances

ReadFractional Double

ReadFractional Float

ReadFractional Rational

fractional :: (ReadFractional r, Source s) => s -> Maybe (r, s)

convert bytestring into unsigned fractional using radix.

this function can parse

• oct/hexa-decimal (0o,0O,0x,0X) (optional)
• fractional(0.1, 12224.3543)
• exponential (e1, E+2, e-123) (10-radixed only, optional)

>>> fractional "12.4" :: Maybe (Double, S.ByteString)
Just (12.4,"")
>>> fractional "1.23e12" :: Maybe (Double, L.ByteString)
Just (1.23e12,"")
>>> fractional "0o0.4" :: Maybe (Double, S.ByteString)
Just (0.5,"")
>>> fractional "0x3f.12" :: Maybe (Double, L.ByteString)
Just (63.0703125,"")

double :: Source s => s -> Maybe (Double, s)

double = fractional

integral

integral :: (Num n, Source s) => s -> Maybe (n, s)

integral = integral' (Proxy :: Proxy 10)

int :: Source s => s -> Maybe (Int, s)

int = integral

common

signed :: (Source s, Num r) => (s -> Maybe (r, s)) -> s -> Maybe (r, s)

convert unsigned parser to signed parser.

this function can parse

• sign (+, -) (optional)

>>> signed double ("12.4" :: S.ByteString)
Just (12.4,"")
>>> signed double ("-3.21e3" :: L.ByteString)
Just (-3210.0,"")
>>> signed double ("+0x1f.4" :: S.ByteString)
Just (31.25,"")

DEPRECATED

module Data.ByteString.Read.DEPRECATED