Box.Csv

A csv process based on attoparsec and the box library

Documentation

data CsvConfig

csv file configuration

Constructors

CsvConfig

Fields

• name :: Text

  file name stem

• suffix :: Text

  file suffix

• dir :: Text

  directory

• fsep :: Char

  field separator

• header :: Header

  nature of header row(s)

Instances

Eq CsvConfig

Defined in Box.Csv

Methods

(==) :: CsvConfig -> CsvConfig -> Bool

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

Show CsvConfig

Defined in Box.Csv

Methods

showsPrec :: Int -> CsvConfig -> ShowS

show :: CsvConfig -> String

showList :: [CsvConfig] -> ShowS

Generic CsvConfig

Defined in Box.Csv

Associated Types

type Rep CsvConfig :: Type -> Type

Methods

from :: CsvConfig -> Rep CsvConfig x

to :: Rep CsvConfig x -> CsvConfig

type Rep CsvConfig

Defined in Box.Csv

type Rep CsvConfig = D1 ('MetaData "CsvConfig" "Box.Csv" "box-csv-0.0.3-L6hWntZV0UGFOfOxcCfQkQ" 'False) (C1 ('MetaCons "CsvConfig" 'PrefixI 'True) ((S1 ('MetaSel ('Just "name") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text) :*: S1 ('MetaSel ('Just "suffix") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text)) :*: (S1 ('MetaSel ('Just "dir") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Text) :*: (S1 ('MetaSel ('Just "fsep") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Char) :*: S1 ('MetaSel ('Just "header") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Header)))))

defaultCsvConfig :: CsvConfig

default csv file details

>>> defaultCsvConfig
CsvConfig {name = "time_series_covid19_deaths_global_narrow", suffix = ".csv", dir = "./other", fsep = ',', header = HasHXL}

test data from https://data.humdata.org/dataset/novel-coronavirus-2019-ncov-cases

file :: CsvConfig -> FilePath

filepath for the config.

>>> file defaultCsvConfig
"./other/time_series_covid19_deaths_global_narrow.csv"

data Header

Type of header rows. Note the modern propensity for multiple header rows.

Constructors

HasHeader

HasHXL

NoHeader

Instances

Eq Header

Defined in Box.Csv

Methods

(==) :: Header -> Header -> Bool

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

Show Header

Defined in Box.Csv

Methods

showsPrec :: Int -> Header -> ShowS

show :: Header -> String

showList :: [Header] -> ShowS

rowEmitter :: CsvConfig -> (Char -> Parser a) -> Cont IO (Emitter IO (Either Text a))

A continuation emitter of parsed csv rows from a CsvConfig, returning the original text on failure >>> rowEmitter defaultCsvConfig fields with emit Just (Right ["ProvinceState","CountryRegion",Lat,Long,Date,Value,"ISO 3166-1 Alpha 3-Codes","Region Code","Sub-region Code","Intermediate Region Coder"])

rowCommitter :: CsvConfig -> (a -> [Text]) -> Cont IO (Committer IO a)

commits printed csv rows

>>> let testConfig = CsvConfig "test" ".csv" "./test" ',' NoHeader
>>> let ctest = rowCommitter testConfig (fmap (Text.intercalate "," . fmap show))
>>> ctest `with` (\c -> commit c [[1..10::Int]])
True

>>> rowEmitter testConfig ints `with` emit
Just (Right [1,2,3,4,5,6,7,8,9,10])

runCsv :: CsvConfig -> (Char -> Parser a) -> IO [Either Text a]

Run a parser across all lines of a file.

>>> r1 <- runCsv defaultCsvConfig fields
>>> length r1
42562

>>> length [x | (Left x) <- r1]
0

>>> take 2 $ drop 2 [x | (Right x) <- r1]
[["","Afghanistan","33.0","65.0","2020-06-29","733","AFG","142","34","\r"],["","Afghanistan","33.0","65.0","2020-06-28","721","AFG","142","34","\r"]]

parsers

sep :: Char -> Parser ()

Most parsing and building routines implicity assume a character acting as a separator of fields, and newlines separating rows.

>>> A.parse (sep ',') ",ok"
Done "ok" ()

field_ :: Char -> Parser Text

an unquoted field Does not consume the separator token

>>> A.parse (field_ ',') "field,ok"
Done ",ok" "field"

field :: Char -> Parser Text

an unquoted field Consume the separator token

>>> A.parse (field ',') "field,ok"
Done "ok" "field"

skipField_ :: Char -> Parser ()

skipping a field

>>> A.parse (skipField_ ',') "field,ok"
Done ",ok" ()

skipField :: Char -> Parser ()

skipping a field

>>> A.parse (skipField ',') "field,ok"
Done "ok" ()

int :: Parser Int

int parser

>>> A.parse int "234,ok"
Done ",ok" 234

int' :: Char -> Parser Int

int parser, consumes separator

>>> A.parse (int' ',') "234,ok"
Done "ok" 234

double :: Parser Double

Parse a rational number.

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, if you feed an empty continuation to the first result:

rational "3"     == Done 3.0 ""
rational "3.1"   == Done 3.1 ""
rational "3e4"   == Done 30000.0 ""
rational "3.1e4" == Done 31000.0, ""

Examples with behaviour identical to read:

rational ".3"    == Fail "input does not start with a digit"
rational "e3"    == Fail "input does not start with a digit"

Examples of differences from read:

rational "3.foo" == Done 3.0 ".foo"
rational "3e"    == Done 3.0 "e"

This function does not accept string representations of "NaN" or "Infinity".

double' :: Char -> Parser Double

double parser, consumes separator

>>> A.parse (double' ',') "234.000,ok"
Done "ok" 234.0

fields :: Char -> Parser [Text]

Parser for a csv row of [Text]. TODO: deal with potential for an extra 'r'

>>> A.parseOnly (fields ',') "field1,field2\r"
Right ["field1","field2\r"]

scis :: Char -> Parser [Scientific]

parser for a csv row of [Scientific]

>>> A.parseOnly (scis ',') "1,2.2,3.3"
Right [1.0,2.2,3.3]

ints :: Char -> Parser [Int]

parser for a csv row of [Int]

>>> A.parseOnly (ints ',') "1,2,3"
Right [1,2,3]

doubles :: Char -> Parser [Double]

parser for a csv row of [Double]

>>> A.parseOnly (doubles ',') "1,2,3"
Right [1.0,2.0,3.0]

day' :: Char -> Parser Day

Day parser, consumes separator

>>> A.parse (day' ',') "2020-07-01,ok"
Done "ok" 2020-07-01

tod' :: Char -> Parser TimeOfDay

TimeOfDay parser, consumes separator

>>> A.parse (tod' ',') "23:52:05.221109,ok"
Done "ok" 23:52:05.221109

localtime' :: Char -> Parser LocalTime

TimeOfDay parser, consumes separator

>>> A.parse (localtime' ',') "Jun 24 8:24AM,ok"
Done "ok" 2020-06-24 08:24:00