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Today's Topics:
1. Re: Installing Idris for Linux Dummies: "The following
packages are likely to be broken..." (Norbert Melzer)
2. Re: Installing Idris for Linux Dummies: "The following
packages are likely to be broken..." (Manny Romero)
3. Re: Is it possible to "run" JSON Parser? (David McBride)
4. Re: Installing Idris for Linux Dummies: "The following
packages are likely to be broken..." (David McBride)
----------------------------------------------------------------------
Message: 1
Date: Tue, 29 Aug 2017 16:17:31 +0000
From: Norbert Melzer <timmel...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] Installing Idris for Linux Dummies:
"The following packages are likely to be broken..."
Message-ID:
<ca+bcvstx2jrquv+u+wmw3x4f06sdvrx50mlz_rn_txf2vib...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Manny Romero <mannyrom...@mail.com> schrieb am Di., 29. Aug. 2017 um
15:03 Uhr:
> I am a Linux user (Mint 18) trying to install Idris. I don't know the
> slightest thing about computers.
>
Sorry I have to ask… But if you do not know anything about computers as you
said, why do you want to install Idris?
> I barely managed to install Linux, and later the full GHC, based on ample
> instructions available on the Web. (Still don't actually recall how I did
> it!)
>
Installing Linux (the mainstream distributions at least) is not different
from installing windows… Insert CD, select language, select username, wait,
be happy…
I really do not want to hurt your feelings, but why are you wading through
these things you do not understand? Can't you try something else which is
just slightly out of your comfort zone? Or find someone in your area
guiding you through everything?
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Message: 2
Date: Tue, 29 Aug 2017 18:24:15 +0200
From: "Manny Romero" <mannyrom...@mail.com>
To: "David McBride" <toa...@gmail.com>, "Haskell Beginners"
<beginners@haskell.org>
Subject: Re: [Haskell-beginners] Installing Idris for Linux Dummies:
"The following packages are likely to be broken..."
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Message: 3
Date: Tue, 29 Aug 2017 12:27:34 -0400
From: David McBride <toa...@gmail.com>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <beginners@haskell.org>
Subject: Re: [Haskell-beginners] Is it possible to "run" JSON Parser?
Message-ID:
<can+tr43zk+5otph6dxub3edo_9gnecxok0neymsrkbec3mu...@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
There are three ways to go about this.
Method one, we could turn all the Values into Maybe MyTypes.
Method two, we could filter out any Value which cannot be turned into an MyType.
Method three, we could fail to parse entirely if any Value cannot be
turned into a MyType succesfully.
Here is some code that demonstrates all three approaches.
import Data.Aeson
import Data.Aeson.Types (Parser)
import Control.Monad
import qualified Data.Text as T
import Data.Maybe (catMaybes)
data Resp = Resp {
rHeadings :: [T.Text],
rows1 :: [Maybe MyType],
rows2 :: [MyType],
rows3 :: [MyType]
}
data MyType = MyType
instance FromJSON Resp where
parseJSON = withObject "Resp" $ \v -> do
hds <- v .: "headings"
-- we could catch all of mytypes as maybes
r1 <- fmap f <$> v .: "rows" :: Parser [Maybe MyType]
-- we could throw away values which can't be turned into MyType
r2 <- catMaybes . fmap f <$> v .: "rows" :: Parser [MyType]
-- we could fail the parse entirely if any value fails.
r3 <- v .: "rows" >>= traverse f'
pure $ Resp hds r1 r2 r3
f :: Value -> Maybe MyType
f v = undefined
f' :: Value -> Parser MyType
f' (String t) = pure MyType
f' (Bool t) = pure MyType
f' (Number t) = pure MyType
f' (Null) = pure MyType
-- Anything that is not one of the above will cause a failure of the
entire parse.
f' _ = mzero
On Tue, Aug 29, 2017 at 11:58 AM, Baa <aqua...@gmail.com> wrote:
> Hello List again! :)
>
> If I have a `FromJSON` instance, with `parseJSON` which translates
> `Value` to MyType, how can I run this parser like I "run"
> state/writer/reader monads? I mean not decoding of a bytestring
> representation:
>
> decode::ByteString -> Maybe MyType
>
> but
>
> run::Value -> Maybe MyType
>
> The reason is that I have already collected Value's , and I have
> parsers, so what is the problem, it would seem, to run parser on the
> Value - to convert `Value` into `Maybe MyType`... Is it possible?
>
> ===
> Best regards, Paul
> _______________________________________________
> Beginners mailing list
> Beginners@haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
------------------------------
Message: 4
Date: Tue, 29 Aug 2017 12:31:28 -0400
From: David McBride <toa...@gmail.com>
To: Manny Romero <mannyrom...@mail.com>
Cc: Haskell Beginners <beginners@haskell.org>
Subject: Re: [Haskell-beginners] Installing Idris for Linux Dummies:
"The following packages are likely to be broken..."
Message-ID:
<can+tr41nbngycc9sfkpibtnmsdlyr1t_wq6rn0g8ezpx+av...@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
You are very close. Try apt-get install zlib or possibly apt-get
install zlib-dev. I'm also seeing a possible zlib-bin. This is all
mint specific info, so I can't get any closer than that.
You will not get a .local directory until you succesfully install a
package via stack for the first time.
On Tue, Aug 29, 2017 at 12:24 PM, Manny Romero <mannyrom...@mail.com> wrote:
> stack setup succeeded! But stack install got to 10/90 before:
>
> Process exited with code: ExitFailure 1
> Configuring digest-0.0.1.2...
> Cabal-simple_mPHDZzAJ_1.24.2.0_ghc-8.0.2: Missing dependency on a
> foreign
> library:
> * Missing (or bad) header file: zlib.h
> * Missing C library: z
> This problem can usually be solved by installing the system package that
> provides this library (you may need the "-dev" version). If the library
> is
> already installed but in a non-standard location then you can use the
> flags
> --extra-include-dirs= and --extra-lib-dirs= to specify where it is.
> If the header file does exist, it may contain errors that are caught by
> the C
> compiler at the preprocessing stage. In this case you can re-run
> configure
> with the verbosity flag -v3 to see the error messages.
>
>
> ...Also, I don't seem to have a .local/bin. The only thing I see in .local
> is a folder "share", which seems to have a bunch of things inside that came
> with the Linux distribution (the file manager and so forth). I don't know
> how or if this is related to the problem.
>
> Thanks again. This is really the only place I can think of that could give
> me any hope of getting this installed.
> Sent: Tuesday, August 29, 2017 at 12:01 PM
> From: "David McBride" <toa...@gmail.com>
> To: "Manny Romero" <mannyrom...@mail.com>
> Cc: "Haskell Beginners" <beginners@haskell.org>
> Subject: Re: [Haskell-beginners] Multiline code in GHCi
> Sorry, I should have kept reading. stack setup will most likely
> install ghc without a problem.
>
> Since stack doesn't appear to support your distro, if it doesn't it
> may be because you are missing some of those libraries it mentions.
> It looks like it is based on debian, so you would go apt-get install
> <pkg> the various packages gcc, make, libffi, zlib, libgmp and
> libtinfo.
>
> If stack setup succeeds, then you stack install and after that, you
> should have files in /home/third/.local/bin, one of which is likely
> idris.
>
> Hopefully everything works okay for you!
>
>
> On Tue, Aug 29, 2017 at 11:49 AM, Manny Romero <mannyrom...@mail.com> wrote:
>> Thanks! I don't have the slightest idea what any of this did, with the
>> exception of "cd Idris-dev", but it seems to have worked...up until I got
>> this message:
>>
>> Populated index cache.
>> No compiler found, expected minor version match with ghc-8.0.2 (x86_64)
>> (based on resolver setting in /home/third/Idris-dev/stack.yaml).
>> To install the correct GHC into /home/third/.stack/programs/x86_64-linux/,
>> try running "stack setup" or use the "--install-ghc" flag.
>>
>> ...additionally, I don't seem to have acquired a ~/.local/bin/idris ("no
>> such file or directory"), nor for that matter do I know how to adjust my
>> PATH.
>>
>> Also, for what it may be worth, I had been warned after the "curl -sSL
>> https://get.haskellstack.org/ | sh" that:
>>
>> Detected Linux distribution: linuxmint
>> This installer doesn't support your Linux distribution, trying generic
>> bindist...
>> Stack has been installed to: /usr/local/bin/stack
>> Since this installer doesn't support your Linux distribution,
>> there is no guarantee that 'stack' will work at all! You may
>> need to manually install some system info dependencies for GHC:
>> gcc, make, libffi, zlib, libgmp and libtinfo
>> Please see http://docs.haskellstack.org/en/stable/install_and_upgrade/
>> Pull requests to add support for this distro would be welcome!
>> WARNING: '/home/third/.local/bin' is not on your PATH.
>> For best results, please add it to the beginning of PATH in your
>> profile.
>>
>> ...Sorry to be so completely clueless about the most basic aspects of
>> what's
>> going on, but it really is the state of my knowledge for now!
>>
>>
>> -------------------------
>>
>> Date: Tue, 29 Aug 2017 09:08:35 -0400
>> From: David McBride <toa...@gmail.com>
>> To: The Haskell-Beginners Mailing List - Discussion of primarily
>> beginner-level topics related to Haskell <beginners@haskell.org>
>> Subject: Re: [Haskell-beginners] Installing Idris for Linux Dummies:
>> "The following packages are likely to be broken..."
>> Message-ID:
>> <can+tr41q_g1wpugxpzpjgxnkfp8qc6z1mkyzuurwtx3pu6c...@mail.gmail.com>
>> Content-Type: text/plain; charset="UTF-8"
>>
>> The problem most users face with using straight up cabal is that often
>> the needs of one package conflict with the needs of some of the others
>> you've installed. I highly recommend you use stack to install idris.
>> The process should look something like this:
>>
>> download stack, install it. (directions here:
>> https://docs.haskellstack.org/en/stable/README/)
>> git clone https://github.com/idris-lang/Idris-dev.git
>> cd idris-dev
>> stack install
>>
>> And then either run ~/.local/bin/idris or make sure .local/bin is in
>> your PATH so that you can run idris on the command line.
>>
>> On Tue, Aug 29, 2017 at 9:02 AM, Manny Romero <mannyrom...@mail.com>
>> wrote:
>>> I am a Linux user (Mint 18) trying to install Idris. I don't know the
>>> slightest thing about computers. I barely managed to install Linux, and
>>> later the full GHC, based on ample instructions available on the Web.
>>> (Still
>>> don't actually recall how I did it!)
>>>
>>> Idris, however, seems a little trickier. I followed the website
>>> (https://www.idris-lang.org/download/)'s instructions:
>>>
>>> cabal update
>>> cabal install idris
>>>
>>> ...because apparently I installed "cabal" at some point. But I get this
>>> message, which apparently is quite common:
>>>
>>> cabal: The following packages are likely to be broken by the reinstalls:
>>> semigroupoids-5.1
>>> lens-4.15.1
>>> kan-extensions-5.0.1
>>> profunctors-5.2
>>> comonad-5
>>> bifunctors-5.4.1
>>> Use --force-reinstalls if you want to install anyway.
>>>
>>> ...those are some of my favorite things! I can't live without them! I am
>>> reading things about creating a "sandbox" and so forth. But I cannot use
>>> or
>>> make sense of this information. I don't know the first thing about cabal;
>>> I
>>> never use it; I just load everything into GHCI all the time.
>>>
>>> Does anyone have some *specific* instructions that I can follow (as
>>> "rotely"
>>> and dumbly as possible) to get Idris downloaded so I can use it for some
>>> beginning studies, without breaking Haskell?
>>>
>>> _______________________________________________
>>> Beginners mailing list
>>> Beginners@haskell.org
>>> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>>>
>>
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