31 lines
835 B
Haskell
31 lines
835 B
Haskell
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{-# LANGUAGE BangPatterns #-}
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{-# LANGUAGE DeriveDataTypeable #-}
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{-# LANGUAGE TypeFamilies #-}
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{-# LANGUAGE RebindableSyntax #-}
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{-# LANGUAGE NoImplicitPrelude #-}
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-- |
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-- Module : Basement.NonEmpty
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-- License : BSD-style
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-- Maintainer : Foundation
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-- Stability : experimental
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-- Portability : portable
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--
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-- A newtype wrapper around a non-empty Collection.
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module Basement.NonEmpty
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( NonEmpty(..)
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) where
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import Basement.Exception
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import Basement.Compat.Base
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-- | NonEmpty property for any Collection
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newtype NonEmpty a = NonEmpty { getNonEmpty :: a }
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deriving (Show,Eq)
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instance IsList c => IsList (NonEmpty c) where
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type Item (NonEmpty c) = Item c
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toList = toList . getNonEmpty
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fromList [] = throw NonEmptyCollectionIsEmpty
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fromList l = NonEmpty . fromList $ l
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