18 Oct
2007
18 Oct
'07
1:25 p.m.
On Thu, Oct 18, 2007 at 01:16:37PM +0100, Magnus Therning wrote:
On Thu, Oct 18, 2007 at 20:58:45 +1000, Matthew Brecknell wrote:
For a less hackish solution, you need to do a bit more work. Again, this is untested.
loadAndCheck fn = bracket (openFile fn ReadMode) hClose checkContents checkContents fh = do { s <- hGetContents fh; return $! hasEmpty s }
Note the explicit close, and "return $!" to ensure that hasEmpty has done its work before the file is closed.
Ah, `bracket` is a handy function to know!
Note that you almost never want to use the bracket defined in Haskell98, nor the one in IO.Error. You want the bracket defined in Control.Exception. -- David Roundy Department of Physics Oregon State University