purescript-csv

Simple configurable PureScript CSV parser.

Based on purescript-parsing. Parse list of rows (getting a simple list of fields) or using header row (getting a map from field name to value).

Example (copy into your REPL)

import Prelude

import Text.Parsing.CSV (defaultParsers, makeParsers)
import Text.Parsing.Parser (runParser)

import Data.List
import Data.Either

let isTrue exp = either (\_-> false) (== (exp :: List (List String)))

let testFile = "a,,c,\n,1,2,3\n\"x\",\"field,quoted\",z\n" :: String
let testResult = toList $ toList <$> [["a", "", "c", ""], ["", "1", "2", "3"], ["x", "field,quoted", "z"], [""]]

let parseResult = runParser testFile defaultParsers.file
parseResult
isTrue testResult parseResult

:t runParser testFile defaultParsers.file

If you want to create your own parsers using different field separators, different quotation chars and different line endings (instead of using the defaultParsers) you can do that by

excelParsers = makeParsers '\'' ";" "\r\n"

This will generate a value of type

type Parsers a =
{
  quoted :: (P a -> P a),
  chars :: P String,
  qchars :: P String,
  field :: P String,
  row :: P (List String),
  file :: P (List (List String)),
  fileHeaded :: P (List (M.Map String String))
}

In this specific case using ' as a quotation character a ; as a field seperator and using windows \r\n line seperators instead of the *nix \n.

The easiest and fastest way of course is just to use the defaultParsers who are defined as defaultParsers = makeParsers '"' "," "\n".

nwolverson/purescript-csv

purescript-csv

Example (copy into your REPL)