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You can reach the person managing the list at beginners-ow...@haskell.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Beginners digest..." Today's Topics: 1. "Shortcut" for f (g x) (g x) (Baa) 2. Re: "Shortcut" for f (g x) (g x) (Dániel Arató) 3. Re: "Shortcut" for f (g x) (g x) (Mihai Maruseac) 4. Re: "Shortcut" for f (g x) (g x) (Baa) 5. Re: "Shortcut" for f (g x) (g x) (Jeffrey Brown) 6. Unpacking tuples (mrx) ---------------------------------------------------------------------- Message: 1 Date: Mon, 4 Dec 2017 18:31:02 +0200 From: Baa <aqua...@gmail.com> To: The Haskell-Beginners Mailing List - Discussion of primarily beginner-level topics related to Haskell <beginners@haskell.org> Subject: [Haskell-beginners] "Shortcut" for f (g x) (g x) Message-ID: <20171204183102.23c72c74@Pavel> Content-Type: text/plain; charset=US-ASCII Hello, All! Does Haskell have some "short-form" for such call: `f (g x) (g x)`, for example: compare (snd x) (snd x) Looks like combinatory logic or `ap` but not exactly... === Best regards, Paul ------------------------------ Message: 2 Date: Mon, 4 Dec 2017 17:34:45 +0100 From: Dániel Arató <exitcons...@gmail.com> To: The Haskell-Beginners Mailing List - Discussion of primarily beginner-level topics related to Haskell <beginners@haskell.org> Subject: Re: [Haskell-beginners] "Shortcut" for f (g x) (g x) Message-ID: <CAHvKd2LAzHToZAEQKpNAJ7qJurRh4bExL58sVeboEgeW-0c=n...@mail.gmail.com> Content-Type: text/plain; charset="UTF-8" Hi! I think you're looking for Data.Function.on: http://hackage.haskell.org/package/base-4.10.0.0/docs/Data-Function.html#v:on On 04/12/2017, Baa <aqua...@gmail.com> wrote: > Hello, All! > > Does Haskell have some "short-form" for such call: `f (g x) (g x)`, for > example: > > compare (snd x) (snd x) > > Looks like combinatory logic or `ap` but not exactly... > > === > Best regards, Paul > _______________________________________________ > Beginners mailing list > Beginners@haskell.org > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners > ------------------------------ Message: 3 Date: Mon, 4 Dec 2017 08:34:26 -0800 From: Mihai Maruseac <mihai.marus...@gmail.com> To: The Haskell-Beginners Mailing List - Discussion of primarily beginner-level topics related to Haskell <beginners@haskell.org> Subject: Re: [Haskell-beginners] "Shortcut" for f (g x) (g x) Message-ID: <caomsumj0bo9fzdtvpzz06d2mmeed94tyr47vujblny5-toy...@mail.gmail.com> Content-Type: text/plain; charset="UTF-8" You can use `liftM2 f g g` For the example you mentioned, there's also compare `on` snd or comparing snd with the proper imports (Data.Ord, Data.Function) On Mon, Dec 4, 2017 at 8:31 AM, Baa <aqua...@gmail.com> wrote: > Hello, All! > > Does Haskell have some "short-form" for such call: `f (g x) (g x)`, for > example: > > compare (snd x) (snd x) > > Looks like combinatory logic or `ap` but not exactly... > > === > Best regards, Paul > _______________________________________________ > Beginners mailing list > Beginners@haskell.org > http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners -- Mihai Maruseac (MM) "If you can't solve a problem, then there's an easier problem you can solve: find it." -- George Polya ------------------------------ Message: 4 Date: Mon, 4 Dec 2017 18:51:31 +0200 From: Baa <aqua...@gmail.com> To: beginners@haskell.org Subject: Re: [Haskell-beginners] "Shortcut" for f (g x) (g x) Message-ID: <20171204185131.6e27528a@Pavel> Content-Type: text/plain; charset=US-ASCII Oh, yes! Exactly, thanks to all!! > Hi! > > I think you're looking for Data.Function.on: > http://hackage.haskell.org/package/base-4.10.0.0/docs/Data-Function.html#v:on > > On 04/12/2017, Baa <aqua...@gmail.com> wrote: > > Hello, All! > > > > Does Haskell have some "short-form" for such call: `f (g x) (g x)`, > > for example: > > > > compare (snd x) (snd x) > > > > Looks like combinatory logic or `ap` but not exactly... > > > > === > > Best regards, Paul > > _______________________________________________ > > 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 ------------------------------ Message: 5 Date: Mon, 4 Dec 2017 12:31:40 -0500 From: Jeffrey Brown <jeffbrown....@gmail.com> To: The Haskell-Beginners Mailing List - Discussion of primarily beginner-level topics related to Haskell <beginners@haskell.org> Subject: Re: [Haskell-beginners] "Shortcut" for f (g x) (g x) Message-ID: <caec4ma0t8kw4uji2ubnpaa2uhoqghbupaavxye-zguu0sgr...@mail.gmail.com> Content-Type: text/plain; charset="utf-8" This led me to look up the definition of on <http://hackage.haskell.org/package/base-4.10.0.0/docs/src/Data.Function.html#on> and discover that punctuation can be used as a variable name for an operator! On Mon, Dec 4, 2017 at 11:51 AM, Baa <aqua...@gmail.com> wrote: > Oh, yes! Exactly, thanks to all!! > > > Hi! > > > > I think you're looking for Data.Function.on: > > http://hackage.haskell.org/package/base-4.10.0.0/docs/ > Data-Function.html#v:on > > > > On 04/12/2017, Baa <aqua...@gmail.com> wrote: > > > Hello, All! > > > > > > Does Haskell have some "short-form" for such call: `f (g x) (g x)`, > > > for example: > > > > > > compare (snd x) (snd x) > > > > > > Looks like combinatory logic or `ap` but not exactly... > > > > > > === > > > Best regards, Paul > > > _______________________________________________ > > > 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 > -- Jeff Brown | Jeffrey Benjamin Brown Website <https://msu.edu/~brown202/> | Facebook <https://www.facebook.com/mejeff.younotjeff> | LinkedIn <https://www.linkedin.com/in/jeffreybenjaminbrown>(spammy, so I often miss messages here) | Github <https://github.com/jeffreybenjaminbrown> -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.haskell.org/pipermail/beginners/attachments/20171204/9a3f5a5f/attachment-0001.html> ------------------------------ Message: 6 Date: Mon, 4 Dec 2017 20:05:05 +0100 From: mrx <patrik....@gmail.com> To: The Haskell-Beginners Mailing List - Discussion of primarily beginner-level topics related to Haskell <beginners@haskell.org> Subject: [Haskell-beginners] Unpacking tuples Message-ID: <canzojbg82zupwemsx8fqh7xdsfy+sygqs7+0ooaqzd41idb...@mail.gmail.com> Content-Type: text/plain; charset="utf-8" Hi, If I have a function that produce tuples with three members and I want those members as parameters for a function that takes three parameters. How would I unpack that tuple? It seems that curry does the trick for tuples with two members. How do I do this when there are more than two members? Patrik -------------- next part -------------- An HTML attachment was scrubbed... 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