Safe Haskell | Safe-Inferred |
---|---|
Language | Haskell98 |
Store a stable pointer in a foreign context to be retrieved later. Persists through GHCi reloads. Not thread-safe.
- writeStore :: Store a -> a -> IO ()
- newStore :: a -> IO (Store a)
- lookupStore :: Word32 -> IO (Maybe (Store a))
- readStore :: Store a -> IO a
- deleteStore :: Store a -> IO ()
- storeAction :: Store a -> IO a -> IO a
- withStore :: Store a -> (a -> IO b) -> IO b
- newtype Store a = Store Word32
- data StoreException = StoreNotFound
Foreign stores
writeStore :: Store a -> a -> IO () Source
Write to the store at the given index. If a store doesn't exist,
creates one and resizes the store vector to fit. If there is
already a store at the given index, deletes that store with
deleteStore
before replacing it.
Not thread-safe.
newStore :: a -> IO (Store a) Source
Allocates or finds an unallocated store. The index is random. The internal vector of stores grows in size. When stores are deleted the vector does not shrink, but old slots are re-used.
Not thread-safe.
lookupStore :: Word32 -> IO (Maybe (Store a)) Source
Lookup from the store if an index is allocated.
Not thread-safe.
readStore :: Store a -> IO a Source
Read from the store. If the store has been deleted or is unallocated, this will throw an exception.
Not thread-safe.
deleteStore :: Store a -> IO () Source
Frees the stable pointer for GC and frees up the slot in the store. Deleting an already deleted store is a no-op. But remember that store numbers are re-used.
Not thread-safe.
storeAction :: Store a -> IO a -> IO a Source
Run the action and store the result.
Not thread-safe.
withStore :: Store a -> (a -> IO b) -> IO b Source
Run the action with the value in the store.
Not thread-safe.
A hideously unsafe store. Only for use if you are suave.
data StoreException Source
An exception when working with stores.