 
            Thanks! It really helps.
Regards,
Qingbo Liu
On Dec 7, 2017, 12:31 -0500, Michael Snoyman 
I'm not sure how it happened, but it looks like you ended up with some files in ~/.stack which are linked against a system-wide GHC. In particular:
Library not loaded: /usr/local/opt/ghc/lib/ghc-8.0.2/transformers-0.5.2.0/libHStransformers-0.5.2.0-ghc8.0.2.dylib
The easiest way to fix this is to just wipe out your ~/.stack directory, which will result in having to do some recompiles, but otherwise should be harmless.
On Thu, Dec 7, 2017 at 7:05 PM, Quentin Liu
wrote: What does this output: `which ghc ; stack exec which ghc` `which ghc` gives "ghc not found”, while `stack exec which ghc` gives "/Users/HereWegoR/.stack/programs/x86_64-osx/ghc-8.0.2/bin/ghc”.
What does your stack.yaml look like? For this file I don’t have any stack.yaml. I just wrote the file and tried to load it into ghci.
Do you have a .ghci or other kinds of local configuration file? As far as I can tell, no.
Regards, Qingbo Liu
On Dec 7, 2017, 11:33 -0500, Michael Snoyman
, wrote: Some ideas:
* What does this output: `which ghc ; stack exec which ghc` * What does your stack.yaml look like? * Do you have a .ghci or other kinds of local configuration file?
On Thu, Dec 7, 2017 at 5:42 PM, Quentin Liu
wrote: I am using ghc download and managed by stack. My stack is of the latest version, which is 1.6.1.
Regards, Qingbo Liu
On Dec 7, 2017, 01:56 -0500, Michael Snoyman
, wrote: > What version of Stack are you using (stack --version), and how did you install Stack and GHC? > > It looks like you're using a system-wide GHC installation, which (for reasons like this) we by default no longer use by default in recent Stack releases. > > Upgrading to the latest Stack (via `stack upgrade` or following the instructions at [1]) will probably solve the problem. > > [1] https://haskell-lang.org/get-started/osx > > > On Thu, Dec 7, 2017 at 8:43 AM, Quentin Liu wrote: > > > Hi, > > > > > > I was trying to use Parsec and imported Text.ParserCombinators.Parsec. I could call “stack ghc” to compile the file, but when I loaded the file into ghci and called any function, ghci would report errors > > > > can't load .so/.DLL for: /Users/HereWegoR/.stack/snapshots/x86_64-osx/lts-8.8/8.0.2/lib/x86_64-osx-ghc-8.0.2/libHSmtl-2.2.1-BLKBelFsPB3BoFeSWSOYj6-ghc8.0.2.dylib (dlopen(/Users/HereWegoR/.stack/snapshots/x86_64-osx/lts-8.8/8.0.2/lib/x86_64-osx-ghc-8.0.2/libHSmtl-2.2.1-BLKBelFsPB3BoFeSWSOYj6-ghc8.0.2.dylib, 5): Library not loaded: /usr/local/opt/ghc/lib/ghc-8.0.2/transformers-0.5.2.0/libHStransformers-0.5.2.0-ghc8.0.2.dylib > > > > Referenced from: /Users/HereWegoR/.stack/snapshots/x86_64-osx/lts-8.8/8.0.2/lib/x86_64-osx-ghc-8.0.2/libHSmtl-2.2.1-BLKBelFsPB3BoFeSWSOYj6-ghc8.0.2.dylib > > > > Reason: image not found) > > > > > > > > > > I tried to install transformers by calling `stack install transformers` but the problem still persisted. Is it because the version of transformers in my repo is different from the one referenced by `mtl` package? How should I fix it? > > > > > > Regards, > > > Qingbo Liu > > > > > > _______________________________________________ > > > Beginners mailing list > > > Beginners@haskell.org > > > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners > > > > > _______________________________________________ > Beginners mailing list > Beginners@haskell.org > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners _______________________________________________ Beginners mailing list Beginners@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
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