filter_csv.nim

import os, streams, parsecsv, options, json

type
  Filter = object
    column: string
    `include`: bool
    values: seq
    min: Option[string]
    max: Option[string]
  
  Configuration = ref object
    output: string
    filters: seq[Filter]

proc main() =
  if paramCount() < 2:
    quit("synopsis: " & getAppFilename() & " input config")

  let
    inputFilename = paramStr(1)
    configFilename = paramStr(2)

  var
    inputFile = newFileStream(inputFilename, fmRead)
    configFile = newFileStream(configFilename, fmRead)

  if inputFile == nil:
    quit("cannot open the file " & inputFilename)

  defer: inputFile.close()
  defer: configFile.close()

  let configJson = parseJson(configFile, configFilename)
  let config = to(configJson, seq[Configuration])

  echo len(config)

main()

stacktrace.txt

stack trace: (most recent call last)
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1565, 38) to
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1359, 46) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1410, 33) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1348, 27) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1212, 29) processType
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1169, 34) processFields
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1127, 40) processObjField
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1359, 46) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1412, 27) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1212, 29) processType
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1169, 34) processFields
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1127, 40) processObjField
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1410, 33) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1359, 46) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1412, 27) createConstructor
/usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1269, 11) processType
/usr/local/Cellar/nim/1.0.4/nim/lib/system/assertions.nim(27, 20) failedAssertImpl
/usr/local/Cellar/nim/1.0.4/nim/lib/system/assertions.nim(20, 11) raiseAssert
/usr/local/Cellar/nim/1.0.4/nim/lib/system/fatal.nim(39, 5) sysFatal
/Users/halfdan/Projects/dev/filter-csv.nim/filter_csv.nim(34, 18) template/generic instantiation of `to` from here
/usr/local/Cellar/nim/1.0.4/nim/lib/system/fatal.nim(39, 5) Error: unhandled exception: /usr/local/Cellar/nim/1.0.4/nim/lib/pure/json.nim(1269, 18) `false` Unable to process nnkSym T [AssertionError]