Simon Marlow writes: > I've been thinking about duplicating/replacing Handles for a while. > Here's a possible interface: > > -- |Returns a duplicate of the original handle, with its own buffer > -- and file pointer. The original handle's buffer is flushed, > including > -- discarding any input data, before the handle is duplicated. > hDuplicate :: Handle -> IO Handle > -- |Makes the second handle a duplicate of the first handle. The > -- second handle will be closed first, if it is not already. > hDuplicateTo :: Handle -> Handle -> IO ()
I'm not too sure of the issues here. Some examples that use them would be helpful. The only suggestion I'd make is that the names be something with handle in them: huDupHandle, hDupHandleTo > The remaining questions are: > - Should you be allowed to duplicate a Handle which refers > to a file opened in WriteMode? Haskell 98 forbids having > two Handles pointing to the same file opened for writing, > but IMHO it's quite a reasonable thing to do. If we don't allow > this, then there needs to be another version of hDuplicateTo > which invalidates the original Handle. Why does Haskell 98 make this restriction (I don't think that the library report says why)? Thanks, Bernie. _______________________________________________ Glasgow-haskell-users mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-users
