[htoolkit-users] Re: HSQL patch: instance SqlBind Float

[Frederik E. <fre...@a5...>]

Please apply:

--- HSQL/src/HSQL.hsc   2005-02-22 03:37:23.000000000 -0800
+++ HSQL-modified/src/HSQL.hsc  2005-02-22 03:36:44.000000000 -0800
@@ -606,3 +606,22 @@
                                        return (x:xs)
                                else return []
 
+-- | The 'collectRowsASync' function is just like collectRows, but it
+-- uses unsafeInterleaveIO to in the same manner as hGetContents to
+-- cause rows to be read asynchronously from the database in an
+-- "on-demand" fashion as list elements are accessed in the result.
+collectRowsAsync :: (Statement -> IO a) -> Statement -> IO [a]
+collectRowsAsync act stmt = loop
+      where
+        closeAndThrow e = do closeStatement stmt; throw e
+        loop = unsafeInterleaveIO $ (do
+         success <- catch (fetch stmt) closeAndThrow
+         if success
+            then do
+              x <- catch (act stmt) closeAndThrow
+              xs <- loop
+              return (x:xs)
+            else do
+              closeStatement stmt
+              return [])
+

Thanks,

  Frederik

-- 
Frederik Eaton                         http://ofb.net/~frederik/