- Glasgow-haskell-users

OPTIONS in a literate source file
by Dean Herington 22 Jan '02

22 Jan '02

I can't figure out how to get GHC to recognize my OPTIONS pragmas in a literate source file. Neither > {-# OPTIONS -fglasgow-exts #-} nor {-# OPTIONS -fglasgow-exts #-} works as the first line in the file. Can anybody tell me what I'm doing wrong? Thanks. --Dean

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GHC 5.03 windows
by Ronald Legere 20 Jan '02

20 Jan '02

Greetings, I am not sure if this is the right list... I have installed the GHC-5.03 windows 'release canidate' on windows XP. There is not much else on this particular computer. I have played with some basic things, and with Socket, and so far have not found anything to complain about :) CHeers! __________________________________________________ Do You Yahoo!? Send FREE video emails in Yahoo! Mail! http://promo.yahoo.com/videomail/

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Re: State Transformer
by Ashley Yakeley 19 Jan '02

19 Jan '02

At 2002-01-19 08:16, Marcin 'Qrczak' Kowalczyk wrote: >Here is mine. The same code can work with MVars too, as long as the >order of operations is consistent with the empty/full state. The >empty/full state is real for MVars and imagined for IORef/STRef. Could you simply the interface if you consider (MVar a) to hold a (Maybe a)? class Monad m => Ref m a r | r -> m a where newRef :: a -> m r getRef :: r -> m a setRef :: r -> a -> m () modifyRef :: r -> (a -> m a) -> m () instance Ref (ST s) a (STRef s a) where ... instance Ref IO a (IORef a) where ... instance Ref IO (Maybe a) (MVar a) where ... -- Ashley Yakeley, Seattle WA

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Problem with linker on Windows 2000
by Martin Fowler 19 Jan '02

19 Jan '02

I seem to having a problem in the link phase using ghc 5.02.2 It seems to occur with any program, this one is: module Hello() where main = putStr "Hello World\n" The error message is f:/apps/ghc/libHSstd.a(PrelMain__1.o)(.text+0x16):ghc1780.hc: undefined reference to `__stginit_Main' f:/apps/ghc/libHSstd.a(PrelMain__2.o)(.text+0x4):ghc1780.hc: undefined reference to `Main_main_closure' f:/apps/ghc/libHSstd.a(PrelMain__2.o)(.text+0x2f):ghc1780.hc: undefined reference to `Main_main_closure' I'm running on Windows 2000 not using cygwin and did the default install. I've added the full trace from the -v option below Martin ------------------------------------------------------ Glasgow Haskell Compiler, Version 5.02.2, for Haskell 98, compiled by GHC version 5.02.2 Using package config file: f:\apps\ghc\package.conf ==================== Packages ==================== Package {name = "gmp", import_dirs = [], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = [], extra_libraries = ["gmp"], include_dirs = [], c_includes = [], package_deps = [], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "rts", import_dirs = [], source_dirs = [], library_dirs = ["f:/apps/ghc", "f:/apps/ghc/gcc-lib"], hs_libraries = ["HSrts"], extra_libraries = ["m", "winmm", "wsock32"], include_dirs = ["f:/apps/ghc/include", "f:/apps/ghc/include/mingw"], c_includes = ["Stg.h"], package_deps = ["gmp"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = ["-u", "_PrelBase_Izh_static_info", "-u", "_PrelBase_Czh_static_info", "-u", "_PrelFloat_Fzh_static_info", "-u", "_PrelFloat_Dzh_static_info", "-u", "_PrelPtr_Ptr_static_info", "-u", "_PrelWord_Wzh_static_info", "-u", "_PrelInt_I8zh_static_info", "-u", "_PrelInt_I16zh_static_info", "-u", "_PrelInt_I32zh_static_info", "-u", "_PrelInt_I64zh_static_info", "-u", "_PrelWord_W8zh_static_info", "-u", "_PrelWord_W16zh_static_info", "-u", "_PrelWord_W32zh_static_info", "-u", "_PrelWord_W64zh_static_info", "-u", "_PrelStable_StablePtr_static_info", "-u", "_PrelBase_Izh_con_info", "-u", "_PrelBase_Czh_con_info", "-u", "_PrelFloat_Fzh_con_info", "-u", "_PrelFloat_Dzh_con_info", "-u", "_PrelPtr_Ptr_con_info", "-u", "_PrelStable_StablePtr_con_info", "-u", "_PrelBase_False_closure", "-u", "_PrelBase_True_closure", "-u", "_PrelPack_unpackCString_closure", "-u", "_PrelIOBase_stackOverflow_closure", "-u", "_PrelIOBase_heapOverflow_closure", "-u", "_PrelIOBase_NonTermination_closure", "-u", "_PrelIOBase_BlockedOnDeadMVar_closure", "-u", "_PrelWeak_runFinalizzerBatch_closure", "-u", "___stginit_Prelude"]} Package {name = "std", import_dirs = ["f:/apps/ghc/imports/std"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSstd1", "HSstd2"], extra_libraries = ["HSstd_cbits", "wsock32", "msvcrt", "kernel32", "user32"], include_dirs = [], c_includes = ["HsStd.h"], package_deps = ["rts"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "lang", import_dirs = ["f:/apps/ghc/imports/lang"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSlang"], extra_libraries = ["HSlang_cbits"], include_dirs = [], c_includes = ["HsLang.h"], package_deps = [], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = ["-u", "_Addr_Azh_static_info"]} Package {name = "concurrent", import_dirs = ["f:/apps/ghc/imports/concurrent"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSconcurrent"], extra_libraries = [], include_dirs = [], c_includes = [], package_deps = ["lang"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "data", import_dirs = ["f:/apps/ghc/imports/data"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSdata"], extra_libraries = [], include_dirs = [], c_includes = [], package_deps = ["lang", "util"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "net", import_dirs = ["f:/apps/ghc/imports/net"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSnet"], extra_libraries = [], include_dirs = [], c_includes = ["HsNet.h"], package_deps = ["lang", "text", "concurrent"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "posix", import_dirs = ["f:/apps/ghc/imports/posix"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSposix"], extra_libraries = ["HSposix_cbits"], include_dirs = [], c_includes = ["HsPosix.h"], package_deps = ["lang"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "text", import_dirs = ["f:/apps/ghc/imports/text"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HStext"], extra_libraries = ["HStext_cbits"], include_dirs = [], c_includes = ["HsText.h"], package_deps = ["lang"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "util", import_dirs = ["f:/apps/ghc/imports/util"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSutil"], extra_libraries = ["HSutil_cbits"], include_dirs = [], c_includes = ["HsUtil.h"], package_deps = ["lang", "concurrent"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "hssource", import_dirs = ["f:/apps/ghc/imports/hssource"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HShssource"], extra_libraries = [], include_dirs = [], c_includes = [], package_deps = ["text"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "greencard", import_dirs = ["f:/apps/ghc/imports/greencard"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSgreencard"], extra_libraries = [], include_dirs = [], c_includes = [], package_deps = ["lang"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "win32", import_dirs = ["f:/apps/ghc/imports/win32"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSwin321", "HSwin322"], extra_libraries = ["user32", "gdi32", "winmm", "kernel32", "advapi32"], include_dirs = [], c_includes = [], package_deps = ["lang"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "com", import_dirs = ["f:/apps/ghc/imports/com"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HScom"], extra_libraries = ["user32", "ole32", "oleaut32", "advapi32"], include_dirs = [], c_includes = [], package_deps = ["lang"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} Package {name = "xlib", import_dirs = ["f:/apps/ghc/imports/xlib"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSxlib"], extra_libraries = ["HSxlib_cbits", "X11"], include_dirs = [], c_includes = ["HsXlib.h"], package_deps = ["greencard"], extra_ghc_opts = [], extra_cc_opts = [""], extra_ld_opts = Hsc static flags: -static -fignore-interface-pragmas -fomit-interface-pragmas -fdo-lambda-eta-expansion -flet-no-escape *** Checking old interface for hs = Just "hello.hs", hspp = Just "hello.hs": compilation IS NOT required *** Touching object file f:\apps\ghc\touchy.exe "hello.o" *** Linker f:\apps\ghc\gcc -B"f:\apps\ghc\gcc-lib/" "-v" "-o" "a.out" "-DDONT_WANT_WIN32_DLL_SUPPORT" "-mno-cygwin" "hello.o" "-Lf:/apps/ghc" "-Lf:/apps/ghc/gcc-lib" "-lHSstd" "-lHSstd_cbits" "-lwsock32" "-lmsvcrt" "-lkernel32" "-luser32" "-lHSrts" "-lm" "-lwinmm" "-lwsock32" "-lgmp" "-u" "_PrelBase_Izh_static_info" "-u" "_PrelBase_Czh_static_info" "-u" "_PrelFloat_Fzh_static_info" "-u" "_PrelFloat_Dzh_static_info" "-u" "_PrelPtr_Ptr_static_info" "-u" "_PrelWord_Wzh_static_info" "-u" "_PrelInt_I8zh_static_info" "-u" "_PrelInt_I16zh_static_info" "-u" "_PrelInt_I32zh_static_info" "-u" "_PrelInt_I64zh_static_info" "-u" "_PrelWord_W8zh_static_info" "-u" "_PrelWord_W16zh_static_info" "-u" "_PrelWord_W32zh_static_info" "-u" "_PrelWord_W64zh_static_info" "-u" "_PrelStable_StablePtr_static_info" "-u" "_PrelBase_Izh_con_info" "-u" "_PrelBase_Czh_con_info" "-u" "_PrelFloat_Fzh_con_info" "-u" "_PrelFloat_Dzh_con_info" "-u" "_PrelPtr_Ptr_con_info" "-u" "_PrelStable_StablePtr_con_info" "-u" "_PrelBase_False_closure" "-u" "_PrelBase_True_closure" "-u" "_PrelPack_unpackCString_closure" "-u" "_PrelIOBase_stackOverflow_closure" "-u" "_PrelIOBase_heapOverflow_closure" "-u" "_PrelIOBase_NonTermination_closure" "-u" "_PrelIOBase_BlockedOnDeadMVar_closure" "-u" "_PrelWeak_runFinalizzerBatch_closure" "-u" "___stginit_Prelude" "-u" "_PrelMain_mainIO_closure" "-u" "___stginit_PrelMain" Reading specs from f:/apps/ghc/gcc-lib/specs gcc version 2.95.3-5 (mingw special) f:\apps\ghc\gcc-lib\ld.exe -Bdynamic -o a.out -u _PrelBase_Izh_static_info -u _PrelBase_Czh_static_info -u _PrelFloat_Fzh_static_info -u _PrelFloat_Dzh_static_info -u _PrelPtr_Ptr_static_info -u _PrelWord_Wzh_static_info -u _PrelInt_I8zh_static_info -u _PrelInt_I16zh_static_info -u _PrelInt_I32zh_static_info -u _PrelInt_I64zh_static_info -u _PrelWord_W8zh_static_info -u _PrelWord_W16zh_static_info -u _PrelWord_W32zh_static_info -u _PrelWord_W64zh_static_info -u _PrelStable_StablePtr_static_info -u _PrelBase_Izh_con_info -u _PrelBase_Czh_con_info -u _PrelFloat_Fzh_con_info -u _PrelFloat_Dzh_con_info -u _PrelPtr_Ptr_con_info -u _PrelStable_StablePtr_con_info -u _PrelBase_False_closure -u _PrelBase_True_closure -u _PrelPack_unpackCString_closure -u _PrelIOBase_stackOverflow_closure -u _PrelIOBase_heapOverflow_closure -u _PrelIOBase_NonTermination_closure -u _PrelIOBase_BlockedOnDeadMVar_closure -u _PrelWeak_runFinalizzerBatch_closure -u ___stginit_Prelude -u _PrelMain_mainIO_closure -u ___stginit_PrelMain f:/apps/ghc/gcc-lib/crt2.o -Lf:/apps/ghc -Lf:/apps/ghc/gcc-lib -Lf:/apps/ghc/gcc-lib hello.o -lHSstd -lHSstd_cbits -lwsock32 -lmsvcrt -lkernel32 -luser32 -lHSrts -lm -lwinmm -lwsock32 -lgmp -lmingw32 -lgcc -lmoldname -lmsvcrt -luser32 -lkernel32 -ladvapi32 -lshell32 -lmingw32 -lgcc -lmoldname -lmsvcrt f:/apps/ghc/libHSstd.a(PrelMain__1.o)(.text+0x16):ghc1780.hc: undefined reference to `__stginit_Main' f:/apps/ghc/libHSstd.a(PrelMain__2.o)(.text+0x4):ghc1780.hc: undefined reference to `Main_main_closure' f:/apps/ghc/libHSstd.a(PrelMain__2.o)(.text+0x2f):ghc1780.hc: undefined reference to `Main_main_closure' Failed: f:\apps\ghc\gcc -B"f:\apps\ghc\gcc-lib/" "-v" "-o" "a.out" "-DDONT_WANT_WIN32_DLL_SUPPORT" "-mno-cygwin" "hello.o" "-Lf:/apps/ghc" "-Lf:/apps/ghc/gcc-lib" "-lHSstd" "-lHSstd_cbits" "-lwsock32" "-lmsvcrt" "-lkernel32" "-luser32" "-lHSrts" "-lm" "-lwinmm" "-lwsock32" "-lgmp" "-u" "_PrelBase_Izh_static_info" "-u" "_PrelBase_Czh_static_info" "-u" "_PrelFloat_Fzh_static_info" "-u" "_PrelFloat_Dzh_static_info" "-u" "_PrelPtr_Ptr_static_info" "-u" "_PrelWord_Wzh_static_info" "-u" "_PrelInt_I8zh_static_info" "-u" "_PrelInt_I16zh_static_info" "-u" "_PrelInt_I32zh_static_info" "-u" "_PrelInt_I64zh_static_info" "-u" "_PrelWord_W8zh_static_info" "-u" "_PrelWord_W16zh_static_info" "-u" "_PrelWord_W32zh_static_info" "-u" "_PrelWord_W64zh_static_info" "-u" "_PrelStable_StablePtr_static_info" "-u" "_PrelBase_Izh_con_info" "-u" "_PrelBase_Czh_con_info" "-u" "_PrelFloat_Fzh_con_info" "-u" "_PrelFloat_Dzh_con_info" "-u" "_PrelPtr_Ptr_con_info" "-u" "_PrelStable_StablePtr_con_info" "-u" "_PrelBase_False_closure" "-u" "_PrelBase_True_closure" "-u" "_PrelPack_unpackCString_closure" "-u" "_PrelIOBase_stackOverflow_closure" "-u" "_PrelIOBase_heapOverflow_closure" "-u" "_PrelIOBase_NonTermination_closure" "-u" "_PrelIOBase_BlockedOnDeadMVar_closure" "-u" "_PrelWeak_runFinalizzerBatch_closure" "-u" "___stginit_Prelude" "-u" "_PrelMain_mainIO_closure" "-u" "___stginit_PrelMain" *** Deleting temp files Deleting: E:\DOCUME~1\mfowler\LOCALS~1\Temp/ghc1620.s E:\DOCUME~1\mfowler\LOCALS~1\Temp/ghc1620.hspp Warning: deleting non-existent E:\DOCUME~1\mfowler\LOCALS~1\Temp/ghc1620.s Warning: deleting non-existent E:\DOCUME~1\mfowler\LOCALS~1\Temp/ghc1620.hspp [""]} Package {name = "HGL", import_dirs = ["f:/apps/ghc/imports/HGL"], source_dirs = [], library_dirs = ["f:/apps/ghc"], hs_libraries = ["HSHGL"], extra_libraries = [], include_dirs = [], c_includes = [], package_deps = ["xlib", "concurrent"], extra_ghc_opts = [], extra_cc_opts = [], extra_ld_opts = []} http://www.martinfowler.com

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Re: State Transformer
by Marcin 'Qrczak' Kowalczyk 19 Jan '02

19 Jan '02

11 Jan 2002 17:10:16 -0500, Albert Lai <trebla(a)vex.net> pisze: > Now my grief is that I cannot write a subprogram with state > variables and have it reused in ST and IO. Fortunately I can write > a subprogram with mutable arrays and have it reused in ST and IO, > so I can write "sort a given array"; but I cannot write "increment > a given integer variable". You can if you write your own class describing the common interface. Here is mine. The same code can work with MVars too, as long as the order of operations is consistent with the empty/full state. The empty/full state is real for MVars and imagined for IORef/STRef. module UnifiedRef (Ref(..), STRef, IORef, MVar) where import ST import IOExts import Concurrent class Monad m => Ref m c | c -> m where -- Minimal definition: -- 'newRef' or 'newEmptyRef', -- 'getRef' or 'cutRef', -- 'setRef' or 'insertRef'. newRef :: a -> m (c a) newEmptyRef :: m (c a) copyRef :: c a -> m (c a) getRef :: c a -> m a setRef :: c a -> a -> m () cutRef :: c a -> m a insertRef :: c a -> a -> m () modifyRef :: c a -> (a -> m a) -> m () withRef :: c a -> (a -> m b) -> m b changeRef :: c a -> (a -> m (b, a)) -> m b newRef a = do c <- newEmptyRef; insertRef c a; return c newEmptyRef = newRef (error "Empty reference") copyRef c = newRef =<< getRef c getRef c = do a <- cutRef c; insertRef c a; return a setRef c a = do cutRef c; insertRef c a cutRef = getRef insertRef = setRef modifyRef c f = insertRef c =<< f =<< cutRef c withRef c f = do a <- cutRef c; b <- f a; insertRef c a; return b changeRef c f = do a <- cutRef c; (b, a') <- f a; insertRef c a'; return b instance Ref (ST s) (STRef s) where newRef = newSTRef getRef = readSTRef setRef = writeSTRef instance Ref IO IORef where newRef = newIORef getRef = readIORef setRef = writeIORef instance Ref IO MVar where newRef = newMVar newEmptyRef = newEmptyMVar getRef = readMVar cutRef = takeMVar insertRef = putMVar modifyRef = modifyMVar_ withRef = withMVar changeRef r f = modifyMVar r (\a -> do (b, a') <- f a; return (a', b)) -- __("< Marcin Kowalczyk * qrczak(a)knm.org.pl http://qrczak.ids.net.pl/ \__/ ^^ QRCZAK

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Re: Packages
by Marcin 'Qrczak' Kowalczyk 19 Jan '02

19 Jan '02

Sat, 19 Jan 2002 10:10:22 -0500, Mark Conway Wirt <mark(a)ArsConcero.org> pisze: > I ran into this problem with the mysql DB interface. If you change > "qforeign" to "qforeign-curses" in the first line of the .hi file, it > should work. It won't work unless I changed it each time a module from a different package imports this. And it's wrong: the file belongs to qforeign, only it's not installed as qforeign yet. Anyway, it was an error with some versions of ghc near 5.0, it's a warning now, but I want to get rid of the warning. -- __("< Marcin Kowalczyk * qrczak(a)knm.org.pl http://qrczak.ids.net.pl/ \__/ ^^ QRCZAK

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Packages
by Marcin 'Qrczak' Kowalczyk 19 Jan '02

19 Jan '02

QForeign under ghc consists of several packages with some interdependencies. I'm getting warnings during compilation, e.g.: /usr/local/bin/ghc -c -O -Wall -fglasgow-exts -package lang -package data -package concurrent -package posix -iexamples -ilib -Iexamples -Ilib -package-name qforeign-curses examples/Curses.hs Curses.hsc:1: Warning: Module `QIntegral' is located in package `qforeign-curses' but its interface file claims it is part of package `qforeign' I understand what it means but I don't know how to fix it. QIntegral should be in package qforeign, but's found by -ilib during compilation of other modules which use it because it's not installed yet! Please help. -- __("< Marcin Kowalczyk * qrczak(a)knm.org.pl http://qrczak.ids.net.pl/ \__/ ^^ QRCZAK

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Bilgilendirme Forumu
by HostingTalk Web 19 Jan '02

19 Jan '02

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Re: question about kinds
by Ashley Yakeley 19 Jan '02

19 Jan '02

At 2002-01-18 13:19, Hal Daume III wrote: >In theory, I could write: > >class Traversable d a where > traverse :: d a -> (Maybe a, [d a]) > >instance Traversable Tree a where > traverse (Leaf a) = (Just a, []) > traverse (Branch t1 t2) = (Nothing, [t1,t2]) > >instance Traversable [] a where > traverse [] = (Nothing, []) > traverse (x:xs) = (Just x, [xs]) > >instance (Traversable d (e a), Traversable e a) => Traversable d (e >a) where > traverse = ... > >but then both ghc and hugs complain about overlapping instances, even with >-fallow-overlapping-instances/-fallow-undecidable-instances in ghc and +o >in hugs. Try this: class Traversable t a where -- note no fundep traverse :: t -> (Maybe a, [t]) instance Traversable (Tree a) a where traverse (Leaf a) = (Just a, []) traverse (Branch t1 t2) = (Nothing, [t1,t2]) instance Traversable [a] a where traverse [] = (Nothing, []) traverse (x:xs) = (Just x, [xs]) instance (Traversable (d (e a)) (e a), Traversable (e a) a) => Traversable (d (e a)) a where traverse = ... ...or even, more generally... instance (Traversable a b, Traversable b c) => Traversable a c where traverse = ... -- Ashley Yakeley, Seattle WA

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Re: question about kinds
by Ashley Yakeley 19 Jan '02

19 Jan '02

At 2002-01-18 13:10, Hal Daume III wrote: >Now, I want to say that if some data type 'd' is Traversable and another >data type 'e' is Traversable, then the "combined data type" is >Traversable. That is, for example, I want to say that a Tree of Lists is >traversable, or that a List of Trees, or a List of Lists is traversable. If the Tree type constructor is Traversable, then it's Traversable no matter what it's applied to. You've provided a instance for traversing "Trees of anything", it's going to overlap with any instance for "Trees of Lists". -- Ashley Yakeley, Seattle WA

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