Read instances

[choener]

Hi,

how about Read instances for the library? I like Read/Show a lot for serializing because it costs nothing (cost = my time spent programming that).

Do you want it in the vector library or do you prefer something like "vector-read-instances"? It is a vote because I already have the code for unboxed vectors written. ;-)

{-# LANGUAGE ScopedTypeVariables #-}

-- | Read instance for unboxed vectors.

module Data.Vector.Unboxed.Read where

import qualified Data.Vector.Unboxed as VU
import qualified Text.Read.Lex as L
import GHC.Show
import Text.Read
import Text.ParserCombinators.ReadP

instance (VU.Unbox a, Read a) => Read (VU.Vector a) where
  readPrec =
    parens $ do
        L.Ident "fromList" <- lexP
        (vals :: [a])  <- readPrec
        lift $ skipSpaces
        lift $ string "::"
        lift $ skipSpaces
        lift $ string "Data.Vector.Unboxed.Vector"
        return $ VU.fromList vals
  readListPrec = readListPrecDefault
  readList     = readListDefault

[choener]

Hi,

I needed this public earlier than I expected. I will transfer all the stuff from "vector-read-instances" into a patch in the near future and until then keep the package alive on hackage.

[rl]

If you could do this in the next week or so, it would go into 0.8.

[rl]

Fri Aug 26 23:04:27 BST 2011 Roman Leshchinskiy <rl@…>

• Follow containers convention in Show instances and add Read instances