Send Beginners mailing list submissions to
[email protected]
To subscribe or unsubscribe via the World Wide Web, visit
http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
or, via email, send a message with subject or body 'help' to
[email protected]
You can reach the person managing the list at
[email protected]
When replying, please edit your Subject line so it is more specific
than "Re: Contents of Beginners digest..."
Today's Topics:
1. Re: Beginners Digest, Vol 106, Issue 7 (mike thomas)
----------------------------------------------------------------------
Message: 1
Date: Wed, 19 Apr 2017 14:54:17 +1000
From: mike thomas <[email protected]>
To: The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell <[email protected]>
Subject: Re: [Haskell-beginners] Beginners Digest, Vol 106, Issue 7
Message-ID:
<cafh3cn2b2vjbc2twk0kebt8kn0-nvyw+iu01dncqsxrunsj...@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
I've had good luck recently with Atom and Visual Studio code on Windows 10
and MacOS.
I'm looking at the Haskell-ghc-mod, ide-Haskell and language-Haskell
community packages right now on Atom,
and on VS Code I've got Haskell ghc-mod, Haskell syntax highlighting and
Haskell linter.
I hope this helps.
Also, do please trim stuff from previous posts not relevant to your
question. I can't do it to this reply because I'm on a phone at the
moment, and deleting that much stuff is more trouble than it's worth.
Cheers
Mike
On 19 Apr 2017 10:17 am, "Frank Lugala" <[email protected]> wrote:
Can anyone suggest a good Haskell IDE for windows?
------------------------------
*From:* Beginners <[email protected]> on behalf of David
McBride <[email protected]>
*Sent:* Tuesday, April 18, 2017 4:22 PM
*To:* The Haskell-Beginners Mailing List - Discussion of primarily
beginner-level topics related to Haskell
*Subject:* Re: [Haskell-beginners] Beginners Digest, Vol 106, Issue 7
That depends on what package you are using to parse. If you are using
parsec, you can use the string function from Text.Parsec.Char. If you
are using some other package, it probably has a different name for it.
On Tue, Apr 18, 2017 at 8:39 AM, Andrey Klaus <[email protected]>
wrote:
> Hello everybody,
>
> A small question.
> -----
> packageP = do
> literal “package"
> -----
>
> what is the "literal" in this code? My problem is
>
> $ ghc ParserTest.hs
> [1 of 1] Compiling ParserTest ( ParserTest.hs, ParserTest.o )
>
> ParserTest.hs:11:5: Not in scope: ‘literal’
>
> $ ghc --version
> The Glorious Glasgow Haskell Compilation System, version 7.10.3
>
> Is this because I use old version of software?
>
> Thanks,
> Andrey
>
>
>
> 2017-04-14 21:58 GMT+03:00 <[email protected]>:
>>
>> Send Beginners mailing list submissions to
>> [email protected]
>>
>> To subscribe or unsubscribe via the World Wide Web, visit
>> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
Haskell-Beginners Info Page
<http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners>
mail.haskell.org
Haskell-Beginners -- The Haskell-Beginners Mailing List - Discussion of
primarily beginner-level topics related to Haskell About Haskell-Beginners
>> or, via email, send a message with subject or body 'help' to
>> [email protected]
>>
>> You can reach the person managing the list at
>> [email protected]
>>
>> When replying, please edit your Subject line so it is more specific
>> than "Re: Contents of Beginners digest..."
>>
>>
>> Today's Topics:
>>
>> 1. Parsing (mike h)
>> 2. Re: Parsing (David McBride)
>> 3. Re: Parsing (Francesco Ariis)
>> 4. Re: Parsing (mike h)
>> 5. Re: Parsing (mike h)
>>
>>
>> ----------------------------------------------------------------------
>>
>> Message: 1
>> Date: Fri, 14 Apr 2017 19:02:37 +0100
>> From: mike h <[email protected]>
>> To: The Haskell-Beginners Mailing List - Discussion of primarily
>> beginner-level topics related to Haskell <[email protected]>
>> Subject: [Haskell-beginners] Parsing
>> Message-ID: <[email protected]>
>> Content-Type: text/plain; charset=utf-8
>>
>> I have
>> data PackageDec = Pkg String deriving Show
>>
>> and a parser for it
>>
>> packageP :: Parser PackageDec
>> packageP = do
>> literal “package"
>> x <- identifier
>> xs <- many ((:) <$> char '.' <*> identifier)
>> return $ Pkg . concat $ (x:xs)
>>
>> so I’m parsing for this sort of string
>> “package some.sort.of.name”
>>
>> and I’m trying to rewrite the packageP parser in applicative style. As a
>> not quite correct start I have
>>
>> packageP' :: Parser PackageDec
>> packageP' = literal "package" >> Pkg . concat <$> many ((:) <$> char '.'
>> <*> identifier)
>>
>> but I can’t see how to get the ‘first’ identifier into this sequence -
>> i.e. the bit that corresponds to x <- identifier in the
>> monadic version.
>>
>> in ghci
>> λ-> :t many ((:) <$> char '.' <*> identifier)
>> many ((:) <$> char '.' <*> identifier) :: Parser [[Char]]
>>
>> so I think that somehow I need to get the ‘first’ identifier into a list
>> just after Pkg . concat so that the whole list gets flattened and
>> everybody is happy!
>>
>> Any help appreciated.
>>
>> Thanks
>> Mike
>>
>>
>>
>>
>>
>>
>>
>> ------------------------------
>>
>> Message: 2
>> Date: Fri, 14 Apr 2017 14:17:42 -0400
>> From: David McBride <[email protected]>
>> To: The Haskell-Beginners Mailing List - Discussion of primarily
>> beginner-level topics related to Haskell <[email protected]>
>> Subject: Re: [Haskell-beginners] Parsing
>> Message-ID:
>>
>> <can+tr42ifdf62sxo6wdq32rbaphq+eqtkjeuk-dnr8pdfrs...@mail.gmail.com>
>> Content-Type: text/plain; charset=UTF-8
>>
>> Try breaking it up into pieces. There a literal "package" which is
>> dropped. There is a first identifier, then there are the rest of the
>> identifiers (a list), then those two things are combined somehow (with
>> :).
>>
>> literal "package" *> (:) <$> identifier <*> restOfIdentifiers
>> where
>> restOfIdentifiers :: Applicative f => f [String]
>> restOfIdentifiers = many ((:) <$> char '.' <*> identifier
>>
>> I have not tested this code, but it should be close to what you are
>> looking for.
>>
>> On Fri, Apr 14, 2017 at 2:02 PM, mike h <[email protected]>
>> wrote:
>> > I have
>> > data PackageDec = Pkg String deriving Show
>> >
>> > and a parser for it
>> >
>> > packageP :: Parser PackageDec
>> > packageP = do
>> > literal “package"
>> > x <- identifier
>> > xs <- many ((:) <$> char '.' <*> identifier)
>> > return $ Pkg . concat $ (x:xs)
>> >
>> > so I’m parsing for this sort of string
>> > “package some.sort.of.name”
>> >
>> > and I’m trying to rewrite the packageP parser in applicative style. As
a
>> > not quite correct start I have
>> >
>> > packageP' :: Parser PackageDec
>> > packageP' = literal "package" >> Pkg . concat <$> many ((:) <$> char
>> > '.' <*> identifier)
>> >
>> > but I can’t see how to get the ‘first’ identifier into this sequence -
>> > i.e. the bit that corresponds to x <- identifier in the
>> > monadic version.
>> >
>> > in ghci
>> > λ-> :t many ((:) <$> char '.' <*> identifier)
>> > many ((:) <$> char '.' <*> identifier) :: Parser [[Char]]
>> >
>> > so I think that somehow I need to get the ‘first’ identifier into a
list
>> > just after Pkg . concat so that the whole list gets flattened and
>> > everybody is happy!
>> >
>> > Any help appreciated.
>> >
>> > Thanks
>> > Mike
>> >
>> >
>> >
>> >
>> >
>> > _______________________________________________
>> > Beginners mailing list
>> > [email protected]
>> > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
Haskell-Beginners Info Page
<http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners>
mail.haskell.org
Haskell-Beginners -- The Haskell-Beginners Mailing List - Discussion of
primarily beginner-level topics related to Haskell About Haskell-Beginners
>>
>>
>> ------------------------------
>>
>> Message: 3
>> Date: Fri, 14 Apr 2017 20:35:32 +0200
>> From: Francesco Ariis <[email protected]>
>> To: [email protected]
>> Subject: Re: [Haskell-beginners] Parsing
>> Message-ID: <[email protected]>
>> Content-Type: text/plain; charset=utf-8
>>
>> On Fri, Apr 14, 2017 at 07:02:37PM +0100, mike h wrote:
>> > I have
>> > data PackageDec = Pkg String deriving Show
>> >
>> > and a parser for it
>> >
>> > packageP :: Parser PackageDec
>> > packageP = do
>> > literal “package"
>> > x <- identifier
>> > xs <- many ((:) <$> char '.' <*> identifier)
>> > return $ Pkg . concat $ (x:xs)
>> >
>> > so I’m parsing for this sort of string
>> > “package some.sort.of.name”
>> >
>> > and I’m trying to rewrite the packageP parser in applicative style. As
a
>> > not quite correct start I have
>>
>> Hello Mike,
>>
>> I am not really sure what you are doing here? You are parsing a dot
>> separated list (like.this.one) but at the end you are concatenating all
>> together, why?
>> Are you sure you are not wanting [String] instead of String?
>>
>> If so, Parsec comes with some handy parser combinators [1], maybe one of
>> them could fit your bill:
>>
>> -- should work
>> packageP = literal "package" *> Pkg <$> sepEndBy1 identifier (char
>> '.')
>>
>> [1]
>> https://hackage.haskell.org/package/parsec-3.1.11/docs/Text-
Parsec-Combinator.html
>>
>>
>> ------------------------------
>>
>> Message: 4
>> Date: Fri, 14 Apr 2017 20:12:14 +0100
>> From: mike h <[email protected]>
>> To: The Haskell-Beginners Mailing List - Discussion of primarily
>> beginner-level topics related to Haskell <[email protected]>
>> Subject: Re: [Haskell-beginners] Parsing
>> Message-ID: <[email protected]>
>> Content-Type: text/plain; charset=utf-8
>>
>> Hi David,
>>
>> Thanks but I tried something like that before I posted. I’ll try again
>> maybe I mistyped.
>>
>> Mike
>> > On 14 Apr 2017, at 19:17, David McBride <[email protected]> wrote:
>> >
>> > Try breaking it up into pieces. There a literal "package" which is
>> > dropped. There is a first identifier, then there are the rest of the
>> > identifiers (a list), then those two things are combined somehow (with
>> > :).
>> >
>> > literal "package" *> (:) <$> identifier <*> restOfIdentifiers
>> > where
>> > restOfIdentifiers :: Applicative f => f [String]
>> > restOfIdentifiers = many ((:) <$> char '.' <*> identifier
>> >
>> > I have not tested this code, but it should be close to what you are
>> > looking for.
>> >
>> > On Fri, Apr 14, 2017 at 2:02 PM, mike h <[email protected]>
>> > wrote:
>> >> I have
>> >> data PackageDec = Pkg String deriving Show
>> >>
>> >> and a parser for it
>> >>
>> >> packageP :: Parser PackageDec
>> >> packageP = do
>> >> literal “package"
>> >> x <- identifier
>> >> xs <- many ((:) <$> char '.' <*> identifier)
>> >> return $ Pkg . concat $ (x:xs)
>> >>
>> >> so I’m parsing for this sort of string
>> >> “package some.sort.of.name”
>> >>
>> >> and I’m trying to rewrite the packageP parser in applicative style. As
>> >> a not quite correct start I have
>> >>
>> >> packageP' :: Parser PackageDec
>> >> packageP' = literal "package" >> Pkg . concat <$> many ((:) <$> char
>> >> '.' <*> identifier)
>> >>
>> >> but I can’t see how to get the ‘first’ identifier into this sequence -
>> >> i.e. the bit that corresponds to x <- identifier in the
>> >> monadic version.
>> >>
>> >> in ghci
>> >> λ-> :t many ((:) <$> char '.' <*> identifier)
>> >> many ((:) <$> char '.' <*> identifier) :: Parser [[Char]]
>> >>
>> >> so I think that somehow I need to get the ‘first’ identifier into a
>> >> list just after Pkg . concat so that the whole list gets flattened
and
>> >> everybody is happy!
>> >>
>> >> Any help appreciated.
>> >>
>> >> Thanks
>> >> Mike
>> >>
>> >>
>> >>
>> >>
>> >>
>> >> _______________________________________________
>> >> Beginners mailing list
>> >> [email protected]
>> >> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>> > _______________________________________________
>> > Beginners mailing list
>> > [email protected]
>> > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>>
>>
>>
>> ------------------------------
>>
>> Message: 5
>> Date: Fri, 14 Apr 2017 20:19:40 +0100
>> From: mike h <[email protected]>
>> To: The Haskell-Beginners Mailing List - Discussion of primarily
>> beginner-level topics related to Haskell <[email protected]>
>> Subject: Re: [Haskell-beginners] Parsing
>> Message-ID: <[email protected]>
>> Content-Type: text/plain; charset="utf-8"
>>
>> Hi Francesco,
>> Yes, I think you are right with "Are you sure you are not wanting
[String]
>> instead of String?”
>>
>> I could use Parsec but I’m building up a parser library from first
>> principles i.e.
>>
>> newtype Parser a = P (String -> [(a,String)])
>>
>> parse :: Parser a -> String -> [(a,String)]
>> parse (P p) = p
>>
>> and so on….
>>
>> It’s just an exercise to see how far I can get. And its good fun. So
maybe
>> I need add another combinator or to what I already have.
>>
>> Thanks
>>
>> Mike
>>
>>
>> > On 14 Apr 2017, at 19:35, Francesco Ariis <[email protected]> wrote:
>> >
>> > On Fri, Apr 14, 2017 at 07:02:37PM +0100, mike h wrote:
>> >> I have
>> >> data PackageDec = Pkg String deriving Show
>> >>
>> >> and a parser for it
>> >>
>> >> packageP :: Parser PackageDec
>> >> packageP = do
>> >> literal “package"
>> >> x <- identifier
>> >> xs <- many ((:) <$> char '.' <*> identifier)
>> >> return $ Pkg . concat $ (x:xs)
>> >>
>> >> so I’m parsing for this sort of string
>> >> “package some.sort.of.name”
>> >>
>> >> and I’m trying to rewrite the packageP parser in applicative style. As
>> >> a not quite correct start I have
>> >
>> > Hello Mike,
>> >
>> > I am not really sure what you are doing here? You are parsing a dot
>> > separated list (like.this.one) but at the end you are concatenating all
>> > together, why?
>> > Are you sure you are not wanting [String] instead of String?
>> >
>> > If so, Parsec comes with some handy parser combinators [1], maybe one
of
>> > them could fit your bill:
>> >
>> > -- should work
>> > packageP = literal "package" *> Pkg <$> sepEndBy1 identifier (char
>> > '.')
>> >
>> > [1]
>> > https://hackage.haskell.org/package/parsec-3.1.11/docs/Text-
Parsec-Combinator.html
>> > <https://hackage.haskell.org/package/parsec-3.1.11/docs/Text
-Parsec-Combinator.html>
>> > _______________________________________________
>> > Beginners mailing list
>> > [email protected] <mailto:[email protected]
<[email protected]>>
>> > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>> > <http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners>
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL:
>> <http://mail.haskell.org/pipermail/beginners/attachments/
20170414/66a17133/attachment.html>
>>
>> ------------------------------
>>
>> Subject: Digest Footer
>>
>> _______________________________________________
>> Beginners mailing list
>> [email protected]
>> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>>
>>
>> ------------------------------
>>
>> End of Beginners Digest, Vol 106, Issue 7
>> *****************************************
>
>
>
> _______________________________________________
> Beginners mailing list
> [email protected]
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>
_______________________________________________
Beginners mailing list
[email protected]
http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
_______________________________________________
Beginners mailing list
[email protected]
http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://mail.haskell.org/pipermail/beginners/attachments/20170419/7fbd9e25/attachment.html>
------------------------------
Subject: Digest Footer
_______________________________________________
Beginners mailing list
[email protected]
http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
------------------------------
End of Beginners Digest, Vol 106, Issue 13
******************************************
