ANN: stm-chans: Additional types of channels for STM

[winterkoninkje]

stm-chans 1.0.0

The stm-chans package offers a collection of channel types, similar to TChan but with additional features. In particular it offers these types:

TBChan: Bounded FIFO channels.

When the channel is full, writers will block/retry. This ensures that the writers do not get too far ahead of the readers, which helps to make sure that memory and cpu resources are used responsibly.

TMChan: Closeable FIFO channels.

This is like TChan (Maybe a) but with a monotonicity guarantee that once Nothing is returned all future reads will be Nothing as well.

TBMChan: Bounded Closeable FIFO channels.

This combines the capabilities of TBChan and TMChan.

In addition, the stm-chans package offers a (partial) compatibility layer for some API improvements still making their way into the stm package[1]. These new functions include:

tryReadTChan :: TChan a -> STM (Maybe a)

A version of readTChan which does not retry. Instead it returns Nothing if no value is available.

peekTChan :: TChan a -> STM a

Get the next value from the TChan without removing it, retrying if the channel is empty.

tryPeekTChan :: TChan a -> STM (Maybe a)

A version of peekTChan which does not retry. Instead it returns Nothing if no value is available.

Links

• Homepage: http://code.haskell.org/~wren/
• Hackage: http://hackage.haskell.org/package/stm-chans
• Darcs: http://community.haskell.org/~wren/stm-chans
• Haddock: Darcs version