is Alloc needed for visitChildren?

[ghorn]

I'm using a wrapper to avoid the Alloc requirement for visitChildren:

import qualified Control.Concurrent as CC

visitChildren' :: Cursor -> ChildVisitor a -> Maybe a -> IO (Maybe a, Bool)
visitChildren' cursor0 userVisitor userData0 = do
  m <- CC.newMVar userData0
  let cheaterVisitor cursor parent _ = do
        currentUserData <- CC.takeMVar m
        (newUserData,newUserRetCode) <- userVisitor cursor parent currentUserData
        CC.putMVar m newUserData
        return (Nothing :: Maybe Int, newUserRetCode)
  (_,finalRetCode) <- C.visitChildren cursor0 cheaterVisitor Nothing
  finalData <- CC.takeMVar m
  return (finalData, finalRetCode)

Is this a reasonable thing to do? I don't see a reason to pass the data pointer through the c library when it can be done in haskell.

[chetant]

You're absolutely right, there's no need for passing userdata through visitChildren.
You could also use IORefs. I'll try and remove the Alloc req. when I get a chance.
Thanks for find this issue!

[ghorn]

You are very welcome. Thanks for the bindings!

[sethfowler]

@chetant, I've already removed the Alloc requirement (and the user data parameter) in my branch. Sorry I haven't pushed it into this repo yet; as I mentioned in another bug I'm hoping to get it in sometime this week.

[chetant]

That's great!
On May 5, 2013 11:51 PM, "sfowler" notifications@github.com wrote:

@chetant https://github.com/chetant, I've already removed the Alloc
requirement (and the user data parameter) in my branch. Sorry I haven't
pushed it into this repo yet; as I mentioned in another bug I'm hoping to
get it in sometime this week.

—
Reply to this email directly or view it on GitHubhttps://github.com//issues/19#issuecomment-17465405
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[sethfowler]

@ghorn, please see the llvm3.3 branch. Alloc has been removed.