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"
)
