Copyright | (c) Dong Han 2017-2019 |
---|---|
License | BSD |
Maintainer | winterland1989@gmail.com |
Stability | experimental |
Portability | non-portable |
Safe Haskell | None |
Language | Haskell2010 |
Textual numeric parsers.
Synopsis
- uint :: forall a. (Integral a, Bounded a) => Parser a
- int :: forall a. (Integral a, Bounded a) => Parser a
- integer :: Parser Integer
- uint_ :: forall a. (Integral a, Bounded a) => Parser a
- int_ :: (Integral a, Bounded a) => Parser a
- digit :: Parser Int
- hex :: forall a. (Integral a, FiniteBits a) => Parser a
- hex' :: forall a. (Integral a, FiniteBits a) => Parser a
- hex_ :: (Integral a, Bits a) => Parser a
- rational :: Fractional a => Parser a
- float :: Parser Float
- double :: Parser Double
- scientific :: Parser Scientific
- scientifically :: (Scientific -> a) -> Parser a
- rational' :: Fractional a => Parser a
- float' :: Parser Float
- double' :: Parser Double
- scientific' :: Parser Scientific
- scientifically' :: (Scientific -> a) -> Parser a
- w2iHex :: Integral a => Word8 -> a
- w2iDec :: Integral a => Word8 -> a
- hexLoop :: forall a. (Integral a, Bits a) => a -> Bytes -> a
- decLoop :: Integral a => a -> Bytes -> a
- decLoopIntegerFast :: Bytes -> Integer
- floatToScientific :: Float -> Scientific
- doubleToScientific :: Double -> Scientific
Decimal
uint :: forall a. (Integral a, Bounded a) => Parser a Source #
Parse and decode an unsigned decimal number.
Will fail in case of overflow.
int :: forall a. (Integral a, Bounded a) => Parser a Source #
Parse a decimal number with an optional leading '+'
or '-'
sign
character.
This parser will fail if overflow happens.
uint_ :: forall a. (Integral a, Bounded a) => Parser a Source #
Same with uint
, but sliently cast in case of overflow.
int_ :: (Integral a, Bounded a) => Parser a Source #
Same with int
, but sliently cast if overflow happens.
Hex
hex :: forall a. (Integral a, FiniteBits a) => Parser a Source #
Parse and decode an unsigned hex number, fail if input length is larger than (bit_size/4). The hex digits
'a'
through 'f'
may be upper or lower case.
This parser does not accept a leading "0x"
string, and consider
sign bit part of the binary hex nibbles, e.g.
>>>
parse' hex "FF" == Right (-1 :: Int8)
>>>
parse' hex "7F" == Right (127 :: Int8)
>>>
parse' hex "7Ft" == Right (127 :: Int8)
>>>
parse' hex "7FF" == Left ["Z.Data.Parser.Numeric.hex","hex numeric number overflow"]
hex' :: forall a. (Integral a, FiniteBits a) => Parser a Source #
Same with hex
, but only take as many as (bit_size/4) bytes.
>>>
parse' hex "FF" == Right (-1 :: Int8)
>>>
parse' hex "7F" == Right (127 :: Int8)
>>>
parse' hex "7Ft" == Right (127 :: Int8)
>>>
parse' hex "7FF" == Right (127 :: Int8)
hex_ :: (Integral a, Bits a) => Parser a Source #
Same with hex
, but silently cast in case of overflow.
>>>
parse' hex "FF" == Right (-1 :: Int8)
>>>
parse' hex "7F" == Right (127 :: Int8)
>>>
parse' hex "7Ft" == Right (127 :: Int8)
>>>
parse' hex "7FF" == Right (-1 :: Int8)
Fractional
rational :: Fractional a => Parser a Source #
Parse a rational number.
The syntax accepted by this parser is the same as for double
.
Note: this parser is not safe for use with inputs from untrusted
sources. An input with a suitably large exponent such as
"1e1000000000"
will cause a huge Integer
to be allocated,
resulting in what is effectively a denial-of-service attack.
In most cases, it is better to use double
or scientific
instead.
double :: Parser Double Source #
Parse a rational number and round to Double
.
This parser accepts an optional leading sign character, followed by
at least one decimal digit. The syntax similar to that accepted by
the read
function, with the exception that a trailing '.'
or
'e'
not followed by a number is not consumed.
Examples with behaviour identical to read
:
parse' double "3" == ("", Right 3.0) parse' double "3.1" == ("", Right 3.1) parse' double "3e4" == ("", Right 30000.0) parse' double "3.1e4" == ("", Right 31000.0)
parse' double ".3" == (".3", Left ParserError) parse' double "e3" == ("e3", Left ParserError)
Examples of differences from read
:
parse' double "3.foo" == (".foo", Right 3.0) parse' double "3e" == ("e", Right 3.0) parse' double "-3e" == ("e", Right -3.0)
This function does not accept string representations of "NaN" or "Infinity".
scientific :: Parser Scientific Source #
Parse a scientific number.
The syntax accepted by this parser is the same as for double
.
scientifically :: (Scientific -> a) -> Parser a Source #
Parse a scientific number and convert to result using a user supply function.
The syntax accepted by this parser is the same as for double
.
Stricter fractional(rfc8259)
rational' :: Fractional a => Parser a Source #
Parse a rational number.
The syntax accepted by this parser is the same as for double'
.
Note: this parser is not safe for use with inputs from untrusted
sources. An input with a suitably large exponent such as
"1e1000000000"
will cause a huge Integer
to be allocated,
resulting in what is effectively a denial-of-service attack.
In most cases, it is better to use double'
or scientific'
instead.
double' :: Parser Double Source #
More strict number parsing(rfc8259).
scientific
support parse 2314.
and 21321exyz
without eating extra dot or e
via
backtrack, this is not allowed in some strict grammer such as JSON, so we make an
non-backtrack strict number parser separately using LL(1) lookahead. This parser also
agree with read
on extra dot or e handling:
parse' double "3.foo" == Left ParseError parse' double "3e" == Left ParseError
Leading zeros or +
sign is also not allowed:
parse' double "+3.14" == Left ParseError parse' double "0014" == Left ParseError
If you have a similar grammer, you can use this parser to save considerable time.
number = [ minus ] int [ frac ] [ exp ] decimal-point = %x2E ; . digit1-9 = %x31-39 ; 1-9 e = %x65 / %x45 ; e E exp = e [ minus / plus ] 1*DIGIT frac = decimal-point 1*DIGIT
This function does not accept string representations of "NaN" or "Infinity". reference: https://tools.ietf.org/html/rfc8259#section-6
scientific' :: Parser Scientific Source #
Parse a scientific number.
The syntax accepted by this parser is the same as for double'
.
scientifically' :: (Scientific -> a) -> Parser a Source #
Parse a scientific number and convert to result using a user supply function.
The syntax accepted by this parser is the same as for double'
.
Misc
decode hex digits sequence within an array.
Decode digits sequence within an array.
This function may overflow if result can't fit into type.
decLoopIntegerFast :: Bytes -> Integer Source #
decode digits sequence within an array.
A fast version to decode Integer
using machine word as much as possible.
floatToScientific :: Float -> Scientific Source #