winterkoninkje: shadowcrane (clean) (Default)
wren romano ([personal profile] winterkoninkje) wrote2011-04-03 11:36 pm
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ANN: stm-chans: Additional types of channels for STM

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.

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