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Today's Topics:
1. Re: Using "cabal test" and getting "cabal: Prelude.read: no
parse" (Brent Yorgey)
2. Re: apply a function to all params of another function
(Julian Birch)
3. Re: Using "cabal test" and getting "cabal: Prelude.read: no
parse" (Daniel King)
4. Re: Using "cabal test" and getting "cabal: Prelude.read: no
parse" (Brent Yorgey)
----------------------------------------------------------------------
Message: 1
Date: Tue, 27 May 2014 13:45:52 -0400
From: Brent Yorgey <[email protected]>
To: [email protected]
Subject: Re: [Haskell-beginners] Using "cabal test" and getting
"cabal: Prelude.read: no parse"
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii
This seems related, though I don't think it's your problem exactly:
https://github.com/haskell/cabal/issues/1366
Apparently a "read: no parse" error can be generated when cabal fails
to read a log file for some reason. Can you tell us precisely what
versions of cabal and ghc you are using (i.e. the output of ghc
--version and cabal --version)?
-Brent
On Mon, May 26, 2014 at 11:12:00PM -0400, Daniel King wrote:
> I don't call the `read' function in my source code anywhere. I do
> derive `read' instances in my data definitions, but otherwise grep
> finds no occurrences.
>
> I'm fairly certain this is a bug in the testing framework, but I don't
> know how to debug it further. The cabal compilation process seems to
> produce a file at
> "dist/build/MY_PACKAGE_NAME-testsStub/MY_PACKAGE_NAME-testsStub-tmp/MY_PACKAGE_NAME-testsStub.hs".
> This file contains:
>
> module Main ( main ) where
> import Distribution.Simple.Test ( stubMain )
> import Tests ( tests )
> main :: IO ()
> main = stubMain tests
>
> In the parent directory there is an executable,
> "dist/build/MY_PACKAGE_NAME-testsStub/MY_PACKAGE_NAME-testsStub" which
> appears to be the file which cabal executes when I call "cabal test".
> I'm not sure how this executable is created but I suspect it comes
> from the file I quoted above.
>
> I'm beginning to suspect that the testing framework is not playing
> well with something.
>
> This is my test file: http://lpaste.net/104680
>
> I'm using the detailed-0.9 "type" of test module, because the
> detailed-1.0 "type" isn't present on my system. Is this the problem?
> They seem to reference detailed-1.0 in this user guide I found for
> Cabal: http://www.haskell.org/cabal/release/rc/doc/users-guide/#test-suites
> . Though now, seeing the URL, it seems that the user guide might be
> for a release candidate version of cabal? I found that page through
> googling how to set up a test suite in Cabal.
>
> Can someone point me at a different guide or tutorial? I tried this
> (http://www.haskell.org/cabal/users-guide/) guide as well, but it
> doesn't give any examples and barely references test suites at all.
>
> On Mon, May 26, 2014 at 5:20 PM, Erik Price <[email protected]> wrote:
> > It's possible that you're calling the
> >
> > read :: Read a => String -> a
> >
> > function somewhere with a parameter that the function doesn't know how to
> > parse. I ran into this just today when I called
> >
> > read "a string" :: String
> >
> > when what I needed to call was
> >
> > read "\"a string\"" :: String
> >
> > e
> >
> >
> > On Monday, May 26, 2014, Boris <[email protected]> wrote:
> >>
> >> Hello,
> >>
> >> Last time I got such an error, it was because I was using 'read' for a
> >> type I had defined myself, deriving Read, but on something that was not
> >> reelated to the type. For instance:
> >>
> >> data Foo = Foo deriving (Read, Show)
> >>
> >> x :: Foo
> >> x = read "Bar"
> >>
> >> Do you use read somwhere?
> >>
> >> HTH
> >>
> >> Daniel King <[email protected]> writes:
> >>
> >> > Hi all,
> >> >
> >> > I created a cabal project with the attached cabal file. I run:
> >> >
> >> > cabal configure --enable-tests
> >> > cabal build
> >> > cabal test
> >> >
> >> > and then I get the error:
> >> >
> >> > cabal: Prelude.read: no parse
> >> >
> >> > I'm not sure how to debug this any further. If I execute:
> >> >
> >> > ./dist/build/scientific-pl-testsStub/scientific-pl-testsStub
> >> >
> >> > with any input I've tried (numbers, array notation, string notation,
> >> > etc.) and I get that same error.
> >> >
> >> > I can post the whole project if that is helpful.
> >> >
> >> > Thanks for the debugging tips!
> >> >
> >> > The full log is:
> >> >
> >> > danking@spock # cabal configure --enable-tests
> >> > Resolving dependencies...
> >> > Configuring scientific-pl-0.1.0.0...
> >> > danking@spock # cabal build
> >> > Building scientific-pl-0.1.0.0...
> >> > Preprocessing test suite 'scientific-pl-tests' for
> >> > scientific-pl-0.1.0.0...
> >> > [1 of 3] Compiling SPLData ( SPLData.hs, dist/build/SPLData.o )
> >> > [2 of 3] Compiling SPLEval ( SPLEval.hs, dist/build/SPLEval.o )
> >> > [3 of 3] Compiling Tests ( tests/Tests.hs, dist/build/Tests.o
> >> > )
> >> > In-place registering scientific-pl-tests-0.1.0.0...
> >> > [1 of 1] Compiling Main (
> >> >
> >> > dist/build/scientific-pl-testsStub/scientific-pl-testsStub-tmp/scientific-pl-testsStub.hs,
> >> > dist/build/scientific-pl-testsStub/scientific-pl-testsStub-tmp/Main.o
> >> > )
> >> > Linking dist/build/scientific-pl-testsStub/scientific-pl-testsStub ...
> >> > Preprocessing executable 'scientific-pl' for scientific-pl-0.1.0.0...
> >> > [1 of 3] Compiling SPLData ( SPLData.hs,
> >> > dist/build/scientific-pl/scientific-pl-tmp/SPLData.o )
> >> > [2 of 3] Compiling SPLEval ( SPLEval.hs,
> >> > dist/build/scientific-pl/scientific-pl-tmp/SPLEval.o )
> >> > [3 of 3] Compiling Main ( Main.hs,
> >> > dist/build/scientific-pl/scientific-pl-tmp/Main.o )
> >> > Linking dist/build/scientific-pl/scientific-pl ...
> >> > danking@spock # cabal test
> >> > Running 1 test suites...
> >> > Test suite scientific-pl-tests: RUNNING...
> >> > cabal: Prelude.read: no parse
> >> > 1 danking@spock #
> >>
> >> --
> >> Boris Daix
> >> _______________________________________________
> >> Beginners mailing list
> >> [email protected]
> >> http://www.haskell.org/mailman/listinfo/beginners
> >
> >
> > _______________________________________________
> > Beginners mailing list
> > [email protected]
> > http://www.haskell.org/mailman/listinfo/beginners
> >
>
>
>
> --
> Dan King
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://www.haskell.org/mailman/listinfo/beginners
------------------------------
Message: 2
Date: Tue, 27 May 2014 19:39:46 +0100
From: Julian Birch <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] apply a function to all params of
another function
Message-ID:
<CAB0TuzBzAJouKSwKyYOZC6BgrQaU5JXh+h-rPT7Cqs9=dud...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Just a thought, you might want to use functions like (a,a,a)->a instead.
J
On Monday, May 26, 2014, Brent Yorgey <[email protected]> wrote:
> On Mon, May 26, 2014 at 04:46:29PM +0200, Kees Bleijenberg wrote:
> > In have a lot of functions in a program with params that are alle Int's.
> > f :: Int -> Int -> Int
> > g :: Int -> Int -> Int
> > h :: Int -> Int -> Int -> Int
> > ...
> > and convertParam :: Int -> Int -- say (+1)
> > I want to call functions like f, g and h, but apply convertParam to all
> > params first.
> > f2 a b c = f (convertParam a) (convertParam b) (convertParam c)
> >
> > I tried:
> > run1p f conv = \a -> f (conv a) -- for functions
> with one
> > param
> > run2p f conv = \a b -> f (conv a) (conv b) -- for functions with two
> > params
> > .
> > Can you do this in a more generalized way (using currying?)
> > Any ideas?
>
> class Convertible t where
> convert :: t -> t
>
> instance Convertible Int where
> ...
>
> instance Convertible t => Convertible (Int -> t) where
> ...
>
> I'll let you fill in the ... ! =) Note this only works well because
> the base case is Int. You could also add some extra base cases for
> other concrete return types. However, it is quite difficult to give a
> Convertible instance which applies to "all types which are not
> functions", so this will only work if you are willing to make one
> instance for each concrete result type your functions use.
>
> -Brent
> _______________________________________________
> Beginners mailing list
> [email protected] <javascript:;>
> http://www.haskell.org/mailman/listinfo/beginners
>
--
Sent from an iPhone, please excuse brevity and typos.
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------------------------------
Message: 3
Date: Tue, 27 May 2014 14:47:51 -0400
From: Daniel King <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] Using "cabal test" and getting
"cabal: Prelude.read: no parse"
Message-ID:
<CAOShcWrhsOc9DMcLqrrRYGUTYLq5BR7inpOoO2Vc_UyG=mw...@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8
On Tue, May 27, 2014 at 1:45 PM, Brent Yorgey <[email protected]> wrote:
> This seems related, though I don't think it's your problem exactly:
>
> https://github.com/haskell/cabal/issues/1366
I saw that, realized I didn't change directory at all and wasn't
really sure how to proceed. It did help me narrow done the cause to
something directly in the test suite though.
> Apparently a "read: no parse" error can be generated when cabal fails
> to read a log file for some reason. Can you tell us precisely what
> versions of cabal and ghc you are using (i.e. the output of ghc
> --version and cabal --version)?
Sure thing:
1 danking@spock # cabal --version
cabal-install version 1.20.0.2
using version 1.20.0.0 of the Cabal library
danking@spock # ghc --version
The Glorious Glasgow Haskell Compilation System, version 7.6.3
Upon seeing this version information, I tried changing my build-depends to
depend on Cabal 1.20 or greater, but I still get the error.
--
Dan King
------------------------------
Message: 4
Date: Tue, 27 May 2014 15:29:15 -0400
From: Brent Yorgey <[email protected]>
To: [email protected]
Subject: Re: [Haskell-beginners] Using "cabal test" and getting
"cabal: Prelude.read: no parse"
Message-ID: <[email protected]>
Content-Type: text/plain; charset=us-ascii
On Tue, May 27, 2014 at 02:47:51PM -0400, Daniel King wrote:
> On Tue, May 27, 2014 at 1:45 PM, Brent Yorgey <[email protected]> wrote:
> > This seems related, though I don't think it's your problem exactly:
> >
> > https://github.com/haskell/cabal/issues/1366
>
> I saw that, realized I didn't change directory at all and wasn't
> really sure how to proceed. It did help me narrow done the cause to
> something directly in the test suite though.
>
> > Apparently a "read: no parse" error can be generated when cabal fails
> > to read a log file for some reason. Can you tell us precisely what
> > versions of cabal and ghc you are using (i.e. the output of ghc
> > --version and cabal --version)?
>
> Sure thing:
>
> 1 danking@spock # cabal --version
> cabal-install version 1.20.0.2
> using version 1.20.0.0 of the Cabal library
>
> danking@spock # ghc --version
> The Glorious Glasgow Haskell Compilation System, version 7.6.3
>
> Upon seeing this version information, I tried changing my build-depends to
> depend on Cabal 1.20 or greater, but I still get the error.
Hmm, I'm not sure then. The people who know the most about the
internals of Cabal likely do not read this list; you may have better
luck asking on stackoverflow.com and/or in the #hackage channel on
Freenode IRC.
-Brent
------------------------------
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