bburdette/toop

tuple-like datastructure allowing more than 3 elements.


License
BSD-3-Clause
Install
elm-package install bburdette/toop 1.2.0

Documentation

Toop

A set of tuple-like data structures that allow more than 3 elements.

The main thing I use Toop for is in case statements, to pattern match multiple things at once:

import Toop

case Toop.T4 mba mbb mbc mbd of 
  Toop.T4 (Just a) (Just b) (Just c) (Just d) -> 
    -- we've got all the things!
  _ -> 
    -- failure to get all the things.

applyT functions.

apply calls a function using the Toop elements as the arguments.

args = Toop.T6 "this" 5 "that" 6 (<) "less than"

comp name1 val1 name2 val2 op opname =
  if op val1 val2 then
    name1 ++ " is " ++ opname  ++ name2
  else
    name2 ++ " is " ++ opname  ++ name1

resultString = Toop.Apply.applyT6 comp args

takeT functions:

nums = [1 3 5 2 4 6 8 9]

fiveDmath : Toop.T5 Float Float Float Float Float
fiveDmath args =
  -- some kind of calculation involving exactly 5 numbers

mbresult = (Toop.Take.takeT5 nums) |> Maybe.map fiveDmath

resT functions:

type EditState 
    = MyEdit { uid: Uuid, group: UUID, doc: UUID }
    | Failed String


ToEdit : String -> String -> String -> EditState
ToEdit uid group doc =
    Toop.T3 (UUID.fromString uid) (UUID.fromString group) (UUID.fromString doc)
        |> resT3
        |> Result.map
            (\(Toop.T3 uidid groupid docid) ->
                MyEdit { uid = uidid, group = groupid, doc = docid }
            )
        |> Result.withDefault Failed "invalid uuid"
)