Given a dot-separated Symbol, the typeclass `SplitOnPeriodWrap` will give the last segment of the dot separated symbol.

SplitOnPeriod.purs

module Split where

import Prelude

import Data.Foldable (fold)
import Effect (Effect)
import Effect.Console(log)
import Effect.Unsafe
import Type.Proxy
import Prim.Symbol as Symbol
import Data.Symbol(class IsSymbol)
import Type.Data.Symbol
import Prim.Boolean


class SplitOnPeriod (h :: Symbol) (t :: Symbol) (acc :: Symbol) (last :: Symbol) | h t -> last

-- instance SplitOnPeriod "." t acc acc t
instance 
  (Symbol.Append acc h accPlus)
  => SplitOnPeriod h "" acc accPlus
else instance ( Symbol.Cons h t tail
              , SplitOnPeriod h t "" last
              ) => SplitOnPeriod "." tail acc last
else instance 
    (
        Symbol.Cons h t tail,
        Symbol.Append acc head accPlus,
        SplitOnPeriod h t accPlus last
    ) =>
    SplitOnPeriod head tail acc last

class SplitOnPeriodWrap (inp :: Symbol) (last :: Symbol) | inp -> last
instance 
    (
        Cons h t inp,
        SplitOnPeriod h t "" last
    ) =>
    SplitOnPeriodWrap inp last