>>> :set -XDataKinds -XPolyKinds -XOverloadedStrings
>>> data Proxy s = Proxy
>>> import Text.Read(readMaybe)
>>> import qualified Data.Text as T

1. create path

>>> data Result = A | B T.Text | C | D Int | E T.Text deriving Show

>>> let key = Proxy :: Proxy "key"

>>> let a = root $ exact "foo" $ action Nothing (\_ -> Just A)
>>> let b = root $ exact "bar" $ fetch key Just $ action Nothing (\d -> Just . B $ D.get key d)
>>> let c = root $ exact "bar" $ any $ action (Just "GET") (\_ -> Just C)
>>> let d = root $ exact "bar" $ fetch key (\t -> readMaybe (T.unpack t) :: Maybe Int) $ action Nothing (\d -> Just . D $ D.get key d)
>>> let e = root $ exact "foo" $ fetch key Just $ exact "qux" $ action (Just "POST") (\d -> Just . E $ D.get key d)
>>> a
* /foo
>>> b
* /bar/:key
>>> c
GET /bar/**
>>> d
* /bar/:key
>>> e
POST /foo/:key/qux

1. create router

>>> let r = e +| d +| a +| b +| c +| empty

1. execute router

>>> let run = execute r

>>> run "GET" ["foo"]
Just A
>>> run "GET" ["foo", "bar"]
Nothing
>>> run "GET" ["bar", "12"]
Just (D 12)
>>> run "GET" ["bar", "baz"]
Just (B "baz")
>>> run "GET" ["bar", "baz", "qux"]
Just C
>>> run "POST" ["bar", "baz", "qux"]
Nothing
>>> run "POST" ["foo", "bar", "baz"]
Nothing
>>> run "POST" ["foo", "bar", "qux"]
Just (E "bar")

Store, </, add

Dict, Member, get

KV((:=)), Members