Examples: Parsing sets/flags and enums

[mratsim]

I used cligen for nimbus-launch, a nim project skeleton generator. First of all, awesome work.

Here are some snippets that can be reused as example to parse the following types from the CLI.

type
  License* = enum
    MIT, Apachev2, GPLv2, GPLv3

  Licenses* = set[License]

  TravisConfig* = enum
    StatusDocker, Generic

template argParse*(dst: Licenses, key: string, val: string, help: string) =
  # Parse license input
  let args = val.split(',')
  dst = {}
  for input_license in args:
    var isValid: bool = false
    for supported_license in low(License)..high(License):       # Interesting read: "parseEnum is slow" https://forum.nim-lang.org/t/2949
      if cmpIgnoreStyle(input_license, $supported_license) == 0:
        incl(dst, supported_license)
        isValid = true
    if not isValid:
      argRet(1, "Wrong input license(s) for param \"$1\"\n$2, only MIT, Apachev2, GPLv2 and GPLv3 are supported." %
             [key, help])

template argHelp*(helpT: seq[array[0..3, string]], defVal: Licenses,
                  parNm: string, sh: string, parHelp: string) =
  helpT.add([ keys(parNm, sh), "Licenses", $defVal, parHelp ])


template argParse*(dst: TravisConfig, key: string, val: string, help: string) =
  # Parse TravisConfig input
  var isValid: bool = false
  for supported_config in low(TravisConfig)..high(TravisConfig):       # Interesting read: "parseEnum is slow" https://forum.nim-lang.org/t/2949
    if cmpIgnoreStyle(val, $supported_config) == 0:
      dst = supported_config
      isValid = true
  if not isValid:
    argRet(1, "Wrong input travis config for param \"$1\"\n$2, only StatusDocker and Generic are supported." %
            [key, help])

template argHelp*(helpT: seq[array[0..3, string]], defVal: TravisConfig,
                  parNm: string, sh: string, parHelp: string) =
  helpT.add([ keys(parNm, sh), "Travis: ", $defVal, parHelp ])

[c-blake]

Hey, Mamy. Thanks. Glad you like it. Your code looks good. I should probably have some example code for doing enums.

[c-blake]

Hey. So, I added generic support for any enums. See test/Enums.nim. I have also changed things in a few backward incompatible ways for people defining their own argParse/argHelp like you (see RELEASE_NOTES.md) and added support for seq[T] for almost all the regular T supported by argcvt. I ran into some trouble supporting seq[enum], though...Internal compiler error. Similar generic support for set[T] is probably not so bad, but not as widely applicable since T is more restricted. The internal error has me regretting a bit using templates instead of generic functions, but then the way I let CLI authors pick both the value and type of seqDelimit has me not regretting.

[c-blake]

Ok. Both any enums and any sets of enums should just work by default now. You should be able to just comment out/delete your definitions. There is also a new "+="/"-=" syntax for updating existing values as in --licenses+=MIT. So, I am closing this issue.

I don't know if you have any other user-defined argParse and argHelp, but there have been major changes in how they work. See RELEASE_NOTES.md or argcvt.nim or DETAILS.md. I will soon tag some new release version to cover that backward incompatibility.