Ok, I've been using the -i compile option to specify the folder to some haskell source when I compile using GHC.
ghc -threaded -i/d/haskell/src --make xxx.hs
I understand it uses those files as 'libraries' while compiling but can i do same in GHCi?
I usually import haskell prepackaged lib e.g. import Data.List or :m +Data.List.
I tried import /d/haskell/src -- does not work!
EDIT
From Haskell doc: Chapter 2 Using GHCi
Note that in GHCi, and ––make mode, the -i option is used to specify the search path for source files, whereas in standard batch-compilation mode the -i option is used to specify the search path for interface files.
The '-i' flag is fine, the problem is with loading the module.
Within ghci, :m will only switch to either pre-compiled modules, or modules which were specified on the command-line. You need to use :add MyModule to tell ghci to compile a Haskell source file.
If you have
./src/Module/SubModule.hs
you can load it with the following:
localuser$ ghci -isrc
GHCi, version 7.0.3: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
Prelude> :add Module.SubModule
[1 of 1] Compiling Module.SubModule ( src/Module/SubModule.hs, interpreted )
Ok, modules loaded: Module.SubModule.
*Module.SubModule>
I think you can say :set -i /d/haskell/src; many, but not all, GHC options can be set that way. Alternatively, you should be able to use it as a parameter directly: ghci -i /d/haskell/src.
Related
I installed diagrams, and it seems to be there, but GHCi doesn’t find it. I tried adding the local sandbox to the command line (-package-db), but still no luck.
Any suggestions?
C:\Users\guthrie>
C:\Users\guthrie>cabal install diagrams
Resolving dependencies...
All the requested packages are already installed:
diagrams-1.2
Use --reinstall if you want to reinstall anyway.
I find it in:
C:\Users\guthrie\.cabal-sandbox\i386-windows-ghc-7.6.3-packages.conf.d
(diagrams-1.2, diagrams-contrib, -core, -lib, -svg)
But running: “cabal repl” or using the GHC(i) flag “-package-db=…”
fail to find it:
C:\Users\guthrie>cabal repl
GHCi, version 7.6.3: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Prelude> :m + Diagrams.Prelude
<no location info>:
Could not find module `Diagrams.Prelude'
It is not a module in the current program, or in any known package.
Prelude>
To clarify; ignoring the cabal invocations, using GHC/i directly, and the program diagramsDemo.hs:
-- http://projects.haskell.org/diagrams/doc/quickstart.html
--
import Diagrams.Prelude
import Diagrams.Backend.SVG.CmdLine
main = mainWith (circle 1 :: Diagram B R2)
Gives:
C:\Users\guthrie\Desktop\xFer\Graphics>ghc --make diagramsDemo.hs
diagramsDemo.hs:7:8:
Could not find module `Diagrams.Backend.SVG.CmdLine'
Use -v to see a list of the files searched for.
C:\Users\guthrie\Desktop\xFer\Graphics>ghc --make diagramsDemo.hs -package-db=C:\Users\guthrie\.cabal-sandbox\i386-windows-ghc-7.6.3-packages.conf.d
diagramsDemo.hs:7:8:
Could not find module `Diagrams.Backend.SVG.CmdLine'
Use -v to see a list of the files searched for.
As bheklilr said, if ghci is started with cabal repl, it will only find packages specified as a dependency in the .cabal file.
However you can start it with cabal exec ghci, then it will find all packages installed in the sandbox.
The same is true for invoking ghc (cabal build vs. cabal exec ghc), but note that if you want to pass flags you have to use --, like in cabal exec ghc -- -O2 Main.hs. Alternatively you can use cabal exec bash and launch ghci or ghc in the new shell.
cabal exec was added with Cabal 1.20.
I installed diagrams, and it seems to be there, but GHCi doesn’t find it. I tried adding the local sandbox to the command line (-package-db), but still no luck.
Any suggestions?
C:\Users\guthrie>
C:\Users\guthrie>cabal install diagrams
Resolving dependencies...
All the requested packages are already installed:
diagrams-1.2
Use --reinstall if you want to reinstall anyway.
I find it in:
C:\Users\guthrie\.cabal-sandbox\i386-windows-ghc-7.6.3-packages.conf.d
(diagrams-1.2, diagrams-contrib, -core, -lib, -svg)
But running: “cabal repl” or using the GHC(i) flag “-package-db=…”
fail to find it:
C:\Users\guthrie>cabal repl
GHCi, version 7.6.3: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Prelude> :m + Diagrams.Prelude
<no location info>:
Could not find module `Diagrams.Prelude'
It is not a module in the current program, or in any known package.
Prelude>
To clarify; ignoring the cabal invocations, using GHC/i directly, and the program diagramsDemo.hs:
-- http://projects.haskell.org/diagrams/doc/quickstart.html
--
import Diagrams.Prelude
import Diagrams.Backend.SVG.CmdLine
main = mainWith (circle 1 :: Diagram B R2)
Gives:
C:\Users\guthrie\Desktop\xFer\Graphics>ghc --make diagramsDemo.hs
diagramsDemo.hs:7:8:
Could not find module `Diagrams.Backend.SVG.CmdLine'
Use -v to see a list of the files searched for.
C:\Users\guthrie\Desktop\xFer\Graphics>ghc --make diagramsDemo.hs -package-db=C:\Users\guthrie\.cabal-sandbox\i386-windows-ghc-7.6.3-packages.conf.d
diagramsDemo.hs:7:8:
Could not find module `Diagrams.Backend.SVG.CmdLine'
Use -v to see a list of the files searched for.
As bheklilr said, if ghci is started with cabal repl, it will only find packages specified as a dependency in the .cabal file.
However you can start it with cabal exec ghci, then it will find all packages installed in the sandbox.
The same is true for invoking ghc (cabal build vs. cabal exec ghc), but note that if you want to pass flags you have to use --, like in cabal exec ghc -- -O2 Main.hs. Alternatively you can use cabal exec bash and launch ghci or ghc in the new shell.
cabal exec was added with Cabal 1.20.
I am having some issues using HsLua as a library. Lua compiles just fine as a standalone. And this version runs on my Linux box without a problem. Here is the linking error I see.
GHCi, version 7.4.1: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Prelude> import Scripting.Lua as Lua
Prelude Lua> l <- Lua.newstate
Loading package hslua-0.3.4 ... linking ... <interactive>: C:\..\AppData\Roaming\cabal\hslua-0.3.4\ghc-7.4.1\HShslua-0.3.4.o: unknown symbol `___strtod'
ghc.exe: unable to load package `hslua-0.3.4'
Prelude Lua>
I did some poking around the libraries and found the call for strtod and I think I may have been close but obviously not close enough.
EDIT
This may or may not help. I'll post the cabal file, I made a couple of changes such as adding the os(windows) portion.
Name: hslua
Version: 0.3.4
...
Extra-source-files: src/*.h
Library
Build-depends: base==4.*
Exposed-modules: Scripting.Lua, Scripting.Lua.ConfigFile
Hs-source-dirs: src
C-sources: src/lapi.c, src/lauxlib.c, src/lbaselib.c, src/lcode.c,
src/ldblib.c, src/ldebug.c, src/ldo.c, src/ldump.c, src/lfunc.c,
src/lgc.c, src/linit.c, src/liolib.c, src/llex.c, src/lmathlib.c,
src/lmem.c, src/loadlib.c, src/lobject.c, src/lopcodes.c,
src/loslib.c, src/lparser.c, src/lstate.c, src/lstring.c,
src/lstrlib.c, src/ltable.c, src/ltablib.c, src/ltm.c,
src/lundump.c, src/lvm.c, src/lzio.c, src/ntrljmp.c
Include-dirs: src
ghc-options: -Wall
extensions: ForeignFunctionInterface
if os(linux)
CC-Options: "-DLUA_USE_LINUX"
if os(darwin)
CC-Options: "-DLUA_USE_MACOSX"
if os(freebsd)
CC-Options: "-DLUA_USE_POSIX"
if os(windows)
CC-Options: "-DLUA_BUILD_AS_DLL"
includes: stdlib.h
I tried a couple of different ways to get the stdlib in the project, I've added it in main headers for the project and I've also specified it in the cabal file. Makes me think that is barking up the wrong tree.
EDIT-2
Well I haven't been able to get this built yet on win32. A couple of other things I tried to do that didn't work for me just in case someone else runs into the same problem.
I linked all of the built object files into a static archive and I got the same error as above. I also tried to use a build DLL and I got a different error but I'm not sure if it were progress forwards or backwards.
C:\..\hslua-0.3.4>ghci liblua.dll -package hslua
GHCi, version 7.4.1: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package hslua-0.3.4 ... linking ... ghc.exe: C:\..\hslua-0.3.4\ghc-7.4.1\HShslua-0.3.4.o: unknown symbol `_lua_close'
ghc.exe: unable to load package `hslua-0.3.4'
Hey I was struggling with exactly the same thing on windows and what worked for me was adding the following to the cabal file
if os(windows)
CC-options: "-D__NO_ISOCEXT"
that makes gcc not use the special __strtod but rather just the normal one.
I have a source file that will only compile with Cabal. It's test code, and in the past (before I complicated my Haskell environment) I would run functions from within ghci.
I know ghci can use object files to load code, but when I try to do so I get the following error. So what am I missing?
[mlitchard#Boris Boris_Test]$ ghci /home/mlitchard/Boris_Test/dist/build/Boris_Test/Boris_Test-tmp/Main.o
GHCi, version 7.4.1: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading object (static) /home/mlitchard/Boris_Test/dist/build/Boris_Test/Boris_Test-tmp/Main.o ... done
final link ... ghc: /home/mlitchard/Boris_Test/dist/build/Boris_Test/Boris_Test-tmp/Main.o: unknown symbol
monadzmcontrolzm0zi3zi1zi3_ControlziMonadziTransziControl_zdfMonadBaseControlIOIO_closure'
linking extra libraries/objects failed
When you specify object files manually, GHCi can't tell what the object file depends on, which it would be able to do with .hs files, because it has access to the import ... lines in that situation.
Therefore, you need to add the object files of all the relevant dependencies manually, in this case by adding -package monad-control, when invoking GHCi.
I create a simple module, TestModule.hs, which contains a single exported top-level definition testval = 2. I compile it, creating TestModule.o and TestModule.hi. I delete TestModule.hs. I then load TestModule.o in ghci, like this:
~ λ ghci TestModule.o
GHCi, version 7.0.3.20110517: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package ffi-1.0 ... linking ... done.
Loading object (static) TestModule.o ... done
final link ... done
Prelude>
As you can see, TestModule isn't in scope and I cannot access testval. Why? How can I accomplish this without access to the source file?
Additional question: how do I accomplish the same thing using the hint package?
Thanks!
You can't interpret something that's already been compiled. If you want to interpret it, you need the source. You can make a package, if you like. Instructions are here.