Proposal: Stop using PackedString in template-haskell; drop packedstring as a bootlib

[Simon Marlow]

Proposal ticket here:

   http://hackage.haskell.org/trac/ghc/ticket/3270

Deadline for discussion: June 15 (2 weeks)

Text of the proposal:

The `packedstring` library has been superseded by the `bytestring` and 
`text` libraries, yet we are still shipping it with GHC for only one 
reason: it is used in the representations of three types in 
`template-haskell`.

The proposal is that we

  * make the types `ModName`, `PkgName`, and `OccName` from 
`Language.Haskell.TH.Syntax` into abstract newtypes (an API change)

  * change their representation from `PackedString` to `String`

  * drop the `packedstring` library from the bootlibs that GHC ships with

Relevant discussions:

  * [http://www.haskell.org/pipermail/libraries/2008-November/010960.html]