stm-2.4.3: changelog.md

# Changelog for [`stm` package](http://hackage.haskell.org/package/stm)

## 2.4.3  *Mar 2014*

  * Update behaviour of `newBroadcastTChanIO` to match
    `newBroadcastTChan` in causing an error on a read from the
    broadcast channel

  * Add `mkWeakTVar`

  * Add `isFullTBQueue`

  * Fix `TChan` created via `newBroadcastTChanIO` to throw same
    exception on a `readTChan` as when created via `newBroadcastTChan`

  * Update to Cabal 1.10 format

## 2.4.2  *Nov 2012*

  * Add `Control.Concurrent.STM.TSem` (transactional semaphore)

  * Add Applicative/Alternative instances of STM for GHC <7.0

  * Throw proper exception when `readTChan` called on a broadcast `TChan`

## 2.4  *Jul 2012*

  * Add `Control.Concurrent.STM.TQueue` (a faster `TChan`)

  * Add `Control.Concurrent.STM.TBQueue` (a bounded channel based on `TQueue`)

  * Add `Eq` instance for `TChan`

  * Add `newBroadcastTChan` and `newBroadcastTChanIO`

  * Some performance improvements for `TChan`

  * Add `cloneTChan`