Data.Yaml.Combinators part 2

Contacts.hs

{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE LambdaCase #-}

module Contacts
  ( Contacts,
    contactsParser
  ) where

import Data.Vector (Vector)
import Data.Text (Text)
import Data.Yaml.Combinators

data Contacts = Contacts
  (Vector Person)
  (Vector Organization)
  deriving Show

data Gender = Male
            | Female
            | Unassigned
            deriving Show

data Person = Person
  Text -- name
  Text -- address
  Gender
  deriving Show

data Organization = Organization
  Text -- name
  Text -- address
  deriving Show

contactsParser :: Parser Contacts
contactsParser = object $ Contacts
                 <$> field "persons" personListParser
                 <*> field "organizations" organizationListParser

personListParser :: Parser (Vector Person)
personListParser = array personParser

organizationListParser :: Parser (Vector Organization)
organizationListParser = array organizationParser

personParser :: Parser Person
personParser = object $ Person
               <$> field "name" string
               <*> field "address" string
               <*> field "gender" genderParser

genderParser :: Parser Gender
genderParser =
  fmap (\case "male" -> Male
              "female" -> Female
              _ -> error "gender: shall be either 'male' or 'female'.") string

organizationParser :: Parser Organization
organizationParser = object $ Organization
                     <$> field "name" string
                     <*> field "address" string

input.yaml

persons:
  - name: 'Coco Lenoix'
    address: '1612 Havenhurst Drive'
    gender: 'female'
  - name: 'Diane Selwyn'
    address: '2900 Griffith Park Boulevard'
    gender: 'female'

organizations:
  - name: 'StudioCanal'
    address: '1 Place du Spectacle'
  - name: 'ABC Studios'
    address: '77 West 66th Street'