June 2011 - iPhone - Haskell.org

Has anybody tried Xcode 4 and ghc7 ?
by Pradeep Kumar 13 Sep '11

13 Sep '11

Hello all, I have setup the binaries from ghc-iphone-binary-1.6-sdk-4.2.tar.bz2. I can compile the GetInBehind sample project for the simulator, for compiling for the device however I get errors from the haskell project like /opt/iphone/lib/ghc-6.10.4-iphone/include/Stg.h:54:18: error: math.h: No such file or directory /opt/iphone/lib/ghc-6.10.4-iphone/include/HsFFI.h:31:20: error: stdint.h: No such file or directory /opt/iphone/lib/ghc-6.10.4-iphone/include/HsFFI.h:69:19: error: float.h: No such file or directory In file included from /opt/iphone/lib/ghc-6.10.4-iphone/include/Rts.h:22, /opt/iphone/lib/ghc-6.10.4-iphone/include/RtsExternal.h:43:0: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'forkProcess' /opt/iphone/lib/ghc-6.10.4-iphone/include/gmp.h:519:0: error: expected declaration specifiers or '...' before 'size_t' /opt/iphone/lib/ghc-6.10.4-iphone/include/gmp.h:519:0: error: expected declaration specifiers or '...' before 'size_t' /opt/iphone/lib/ghc-6.10.4-iphone/include/gmp.h:519:0: The only changes I have done to the project is to set the base sdk to ios4.3 and the SDKROOT in Haskell project to iphoneos4.3. The library search paths are set as per "Fix “Library search paths”" in the document. Any hint to what might be the issue? Thank you Pradeep

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Automatically freeing function pointers
by David Pollak 20 Jun '11

20 Jun '11

Howdy, I tried to build a function that would create an auto-freeing function pointer: runOnMain :: IO () -> IO () runOnMain todo = do func <- funky dispatchFunc func where funky = mkStrCB $ \v -> do todo func <- funky freeHaskellFunPtr func Unfortunately, I wind up getting: internal error: iPhoneCreateAdjustor - adjustor pool 'Main_d2K2' is empty (capacity 32) (GHC version 6.10.4-iphone-simulator for i386_apple_darwin) I'm not sure why, but I suspect that funky is being called recursively and thus stuff is never being freed. Any hints as to the issue and solutions? Thanks, David -- Lift, the simply functional web framework http://liftweb.net Simply Lift http://simply.liftweb.net Follow me: http://twitter.com/dpp Blog: http://goodstuff.im

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Thread model questions
by David Pollak 11 Jun '11

11 Jun '11

Howdy, I've got a question about threading and thread models in ghc-iphone. My understanding is that Haskell has its own threading model that under the covers uses OS threads, but allows for significantly more active threads. Is this a correct understanding? If so, how does the Haskell threading model work on the iPhone? Is it that iOS is close enough to OS X/Darwin that it "just works"? If it "just works", then how does one marshal an event back onto the iOS "UI thread" so that the display or draw or whatever command can take place on the UI thread? Is there a convention or recipe for doing so? Would it be possible to put an event on the UI event queue that applies an Haskell closure such that the Haskell code that contains the computed value (I'd force the computation before marshaling the event to minimize the actual delay on the UI thread) then mutates the UI based on the computed value? Given the 5 second rule about an iOS app getting shut down... if there are Haskell threads doing Haskell-y kind of work, is there a way of notifying those threads en masse about the shutdown? Thanks, David -- Lift, the simply functional web framework http://liftweb.net Simply Lift http://simply.liftweb.net Follow me: http://twitter.com/dpp Blog: http://goodstuff.im

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Lisp in Haskell on iPad
by David Pollak 10 Jun '11

10 Jun '11

Howdy all, Okay... got my first iPad app running (super duper big thanks to ghc-iphone): https://github.com/dpp/LispHaskellIPad It's a Lisp interpreter written in Haskell. Enjoy. Thanks, David -- Lift, the simply functional web framework http://liftweb.net Simply Lift http://simply.liftweb.net Follow me: http://twitter.com/dpp Blog: http://goodstuff.im

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ghc-iphone and GHC 7.0.2
by David Pollak 08 Jun '11

08 Jun '11

Howdy, I'm running GHC 7.0.2 on OS X Snow Leopard (64 bit) Is it possible to get ghc-iphone to work with GHC 7? Also, is there a source repository for the ghc-iphone code? Sorry for the dumb/newbie questions. It's the first week in a new environment (Haskell) and I'm feeling my way around and bumping my head a lot. Thanks, David -- Lift, the simply functional web framework http://liftweb.net Simply Lift http://simply.liftweb.net Follow me: http://twitter.com/dpp Blog: http://goodstuff.im

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Haskell Examples
by Ernesto Carrion 01 Jun '11

01 Jun '11

Hi all! I've been dealing with ghc-iphone guide ( http://projects.haskell.org/ghc-iphone/downloads/GHC-iPhone.pdf) I've installed all the binaries and packages but I just can't find the samples (HaskellDraw, GetInBehind) that are suposed to work out of the box. Can someone give me a hint on where can I find those project. PS: Sorry for my crappy english. -- Ernesto M. Carrión

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