[Haskell-beginners] Beginners Digest, Vol 154, Issue 9

Michael Turner michael.eugene.turner at gmail.com
Sat May 22 09:57:49 UTC 2021


That did work, thank you. I wish instructions in the wiki included examples.

A lot of my struggles as a newbie are with

(1) cabal+stack, trying to conform to ways of doing things to get
effects (e.g., perfect reproducibility) I don't even care about right
now, and

(2) documentation that doesn't tell you much about how to make things work.

Regards,
Michael Turner
Executive Director
Project Persephone
1-25-33 Takadanobaba
Shinjuku-ku Tokyo 169-0075
Mobile: +81 (90) 5203-8682
turner at projectpersephone.org

Understand - http://www.projectpersephone.org/
Join - http://www.facebook.com/groups/ProjectPersephone/
Donate - http://www.patreon.com/ProjectPersephone
Volunteer - https://github.com/ProjectPersephone

"Love does not consist in gazing at each other, but in looking outward
together in the same direction." -- Antoine de Saint-Exupéry

On Thu, May 20, 2021 at 9:08 PM <beginners-request at haskell.org> wrote:
>
> Send Beginners mailing list submissions to
>         beginners at haskell.org
>
> 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
>         beginners-request at haskell.org
>
> You can reach the person managing the list at
>         beginners-owner at haskell.org
>
> When replying, please edit your Subject line so it is more specific
> than "Re: Contents of Beginners digest..."
>
>
> Today's Topics:
>
>    1.  Getting debugging going in ghci -- is there no   mercy?
>       (Michael Turner)
>    2. Re:  Getting debugging going in ghci -- is there no mercy?
>       (Francesco Ariis)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Wed, 19 May 2021 21:10:50 +0900
> From: Michael Turner <michael.eugene.turner at gmail.com>
> To: beginners at haskell.org
> Subject: [Haskell-beginners] Getting debugging going in ghci -- is
>         there no        mercy?
> Message-ID:
>         <CANHeBig+dr+GRR-6vVGRHfOxKiEmA+Cff2+tfx+yr_=6cO8v0w at mail.gmail.com>
> Content-Type: text/plain; charset="UTF-8"
>
> According to the Haskell wiki, "The trace function is located in the
> base package", which encouraged me to think it should just work by
> starting ghci. No such luck. So then I tried "stack gchi --package
> debug". No such luck. I added packages to stack.yaml as suggested. And
> here's where I am now.
>
> Of course, I'd like cookbook instructions, but I'm also including all
> this error output to give people an idea of how incredibly
> demoralizing the experience of being a newbie can be. As a newbie,
> it's easy to get confused about what Haskell is actually doing. So
> you'd naturally like a way to inspect intermediate results. Which
> means you'd like tracing and debugging.
>
> Why is it so hard to get there?
>
> -----------
>
>
> C:\Users\Michael Turner\aug\aug.cabal was modified manually. Ignoring
> C:\Users\Michael Turner\aug\package.yaml in favor of the cabal file.
> If you want to use the package.yaml file instead of the cabal file,
> then please delete the cabal file.
>
> Using main module: 1. Package `aug' component aug:exe:aug-exe with
> main-is file: C:\Users\Michael Turner\aug\app\Main.hs
> WARNING: Ignoring transformers-compat's bounds on transformers (>=0.3
> && ==0.2.*); using transformers-0.5.6.2.
> Reason: allow-newer enabled.
>
> Error: While constructing the build plan, the following exceptions were
> encountered:
>
> In the dependencies for Hoed-0.5.1:
>     QuickCheck needed, but the stack configuration has no specified version
>                (latest matching version is 2.14.2)
>     cereal needed, but the stack configuration has no specified version  (latest
>            matching version is 0.5.8.1)
>     cereal-text needed, but the stack configuration has no specified version
>                 (latest matching version is 0.1.0.2)
>     cereal-vector needed, but the stack configuration has no specified version
>                   (latest matching version is 0.2.0.1)
>     primitive needed, but the stack configuration has no specified version
>               (latest matching version is 0.7.1.0)
>     regex-tdfa needed, but the stack configuration has no specified version
>                (latest matching version is 1.3.1.0)
>     regex-tdfa-text needed, but the stack configuration has no specified version
>                     (latest matching version is 1.0.0.3)
>     semigroups needed, but the stack configuration has no specified version
>                (latest matching version is 0.19.1)
>     strict needed, but the stack configuration has no specified version  (latest
>            matching version is 0.4.0.1)
>     terminal-size needed, but the stack configuration has no specified version
>                   (latest matching version is 0.3.2.1)
>     vector-th-unbox needed, but the stack configuration has no specified version
>                     (latest matching version is 0.2.1.9)
> needed due to debug-0.1.1 -> Hoed-0.5.1
>
> In the dependencies for aeson-1.5.6.0:
>     attoparsec must match >=0.13.2.2 && <0.15, but the stack
> configuration has no
>                specified version  (latest matching version is 0.14.1)
>     base-compat-batteries must match >=0.10.0 && <0.12, but the stack
>                           configuration has no specified version
> (latest matching
>                           version is 0.11.2)
>     data-fix must match >=0.3 && <0.4, but the stack configuration has no
>              specified version  (latest matching version is 0.3.1)
>     dlist must match >=0.8.0.4 && <1.1, but the stack configuration has no
>           specified version  (latest matching version is 1.0)
>     primitive must match >=0.7.0.1 && <0.8, but the stack configuration has no
>               specified version  (latest matching version is 0.7.1.0)
>     scientific must match >=0.3.6.2 && <0.4, but the stack configuration has no
>                specified version  (latest matching version is 0.3.6.2)
>     strict must match >=0.4 && <0.5, but the stack configuration has
> no specified
>            version  (latest matching version is 0.4.0.1)
>     tagged must match >=0.8.6 && <0.9, but the stack configuration has no
>            specified version  (latest matching version is 0.8.6.1)
>     th-abstraction must match >=0.2.8.0 && <0.5, but the stack configuration has
>                    no specified version  (latest matching version is 0.4.2.0)
>     these must match >=1.1 && <1.2, but the stack configuration has no specified
>           version  (latest matching version is 1.1.1.1)
>     time-compat must match >=1.9.4 && <1.10, but the stack configuration has no
>                 specified version  (latest matching version is 1.9.5)
>     uuid-types must match >=1.0.3 && <1.1, but the stack configuration has no
>                specified version  (latest matching version is 1.0.5)
> needed due to debug-0.1.1 -> aeson-1.5.6.0
>
> In the dependencies for libgraph-1.14:
>     monads-tf needed, but the stack configuration has no specified version
>               (latest matching version is 0.1.0.3)
>     union-find must match >=0.2, but the stack configuration has no specified
>                version  (latest matching version is 0.2)
> needed due to debug-0.1.1 -> libgraph-1.14
>
> In the dependencies for prettyprinter-compat-ansi-wl-pprint-1.0.1:
>     prettyprinter-ansi-terminal must match >=1.1 && <1.2, but the stack
>                                 configuration has no specified version  (latest
>                                 matching version is 1.1.2)
> needed due to debug-0.1.1 -> prettyprinter-compat-ansi-wl-pprint-1.0.1
>
> In the dependencies for uniplate-1.6.13:
>     syb needed, but the stack configuration has no specified version  (latest
>         matching version is 0.7.2.1)
> needed due to debug-0.1.1 -> uniplate-1.6.13
>
> In the dependencies for vector-0.12.3.0:
>     primitive must match >=0.6.4.0 && <0.8, but the stack configuration has no
>               specified version  (latest matching version is 0.7.1.0)
> needed due to debug-0.1.1 -> vector-0.12.3.0
>
> In the dependencies for yaml-0.11.5.0:
>     attoparsec must match >=0.11.3.0, but the stack configuration has
> no specified
>                version  (latest matching version is 0.14.1)
>     conduit must match >=1.2.8 && <1.4, but the stack configuration has no
>             specified version  (latest matching version is 1.3.4.1)
>     libyaml must match >=0.1 && <0.2, but the stack configuration has
> no specified
>             version  (latest matching version is 0.1.2)
>     resourcet must match >=0.3 && <1.3, but the stack configuration has no
>               specified version  (latest matching version is 1.2.4.2)
>     scientific must match >=0.3, but the stack configuration has no specified
>                version  (latest matching version is 0.3.6.2)
> needed due to debug-0.1.1 -> yaml-0.11.5.0
>
> Some different approaches to resolving this:
>
>   * Recommended action: try adding the following to your extra-deps
>     in C:\Users\Michael Turner\aug\stack.yaml:
>
> - QuickCheck-2.14.2 at sha256:4ce29211223d5e6620ebceba34a3ca9ccf1c10c0cf387d48aea45599222ee5aa,7736
> - attoparsec-0.14.1 at sha256:5a11f0339fb7e65429683e8a36d44adca3fd8cd40704525969c691e359c48fa0,5966
> - base-compat-batteries-0.11.2 at sha256:eb3b976007754ddc16e8d4afacdd1e575ae746edb57dcd0a1a728ccd4b372a69,8804
> - cereal-0.5.8.1 at sha256:37cb7a78c84412e94592a658768320c41f015f2b8707a433de835afb8ebc18d7,2767
> - cereal-text-0.1.0.2 at sha256:dc10e00d9e5047d16a129682aac42c95da188d22e9f85856add051b9ace539c3,1349
> - cereal-vector-0.2.0.1 at sha256:26d8e359f4c0de6dc06bf29f1cc2805847cdd8576d9f1598ecb263a1ca372bec,1116
> - conduit-1.3.4.1 at sha256:eeabaf3f822e3e15317995766f50ef4a20371bdc3bb4721a7541e37228018dcf,5129
> - data-fix-0.3.1 at sha256:7aee2c0633632479cef93c8000befd5bc950ba7c329d69e918ca520944164e27,1645
> - dlist-1.0 at sha256:124cb3aa1decebd5171b46601b1f74cca6cfae12d266ace3799b86dd05ef7cb4,3560
> - libyaml-0.1.2 at sha256:7f14f69ceb14659699974e8e47e1ea6f226ea21ff42a802db03e721c319d201d,2125
> - monads-tf-0.1.0.3 at sha256:25b5d97af98adf7eca709c57f159c6c24c773cbb30e153abaeb156d81a451195,1427
> - prettyprinter-ansi-terminal-1.1.2 at sha256:90b3b7650bc5b9f0e58da43621d23c817acfc0cf5ce71244b9bd11b8c9f95e3a,2653
> - primitive-0.7.1.0 at sha256:29de6bfd0cf8ba023ceb806203dfbec0e51e3524e75ffe41056f70b4229c6f0f,2728
> - regex-tdfa-1.3.1.0 at sha256:eb8d0f007cf45faca8574f56f0d19c9b02bc529ef1688d8f8a9751ce7dc36cc3,6483
> - regex-tdfa-text-1.0.0.3 at sha256:fb72123627eadf43dd5ca74a2896940d50aac291e61f62177960f0563f7d5c03,1180
> - resourcet-1.2.4.2 at sha256:d57516781d1721f70aa0b9ec8ea9200ab02bf76349cb76d73ad57729302289cc,1730
> - scientific-0.3.6.2 at sha256:dd49abc76bd8e2b57e7a057dc2bb742a00527b4bf9350f9374be03b5934e55d8,4679
> - semigroups-0.19.1 at sha256:ecae129621e0d2f77bef2f01e4458c2e0567ab6e1f39579c61d7cec8058ebb0e,6262
> - strict-0.4.0.1 at sha256:08cf72ad570fddfe3b3424117bf20a303a1fb21047b40c1d6c8004c0e3e02a0b,4124
> - syb-0.7.2.1 at sha256:bf42655a213402215299e435c52f799e76cbec0b984cd7153d6b9af8a1c0803f,3815
> - tagged-0.8.6.1 at sha256:5ddf1e324c3cd644f097a48bf490f0bedf467f723fd240afb3ab3b750577f8e7,2874
> - terminal-size-0.3.2.1 at sha256:7b2d8e0475a46961d07ddfb91dee618de70eff55d9ba0402ebeac1f9dcf9b18b,1259
> - th-abstraction-0.4.2.0 at sha256:6ba7b201931f614173755f060fdf98f02095df68c1f7bc3e2691cf9d443e81f9,2194
> - these-1.1.1.1 at sha256:e981c65228db5ae77a043631f74a1e4a4b770f7213866f584e3476b52512f1af,2631
> - time-compat-1.9.5 at sha256:a586bd5a59b47ea0c9eafc55c6936ede11126f4a6e619d6d7aeefee73c43d9b8,4954
> - union-find-0.2 at sha256:22e97cd9aeb8c96bf7cd8d359d4eda635dc0e0a6cd91b9a07e5a203b00949c8d,1232
> - uuid-types-1.0.5 at sha256:5031383749d57cb95877d7e56f0300be66652b6e57f5ba6681dcc6e4f78d046d,2541
> - vector-th-unbox-0.2.1.9 at sha256:5723d9c8a8a941dfeeb59dc42b84b924e4548ab6b5a4afe5b62b39f54667c2dd,1520
>
>
> Error: Plan construction failed.
>
> Warning: Build failed, but trying to launch GHCi anyway
> The following GHC options are incompatible with GHCi and have not been
> passed to it: -threaded
> Configuring GHCi with the following packages: aug
>
> * * * * * * * *
>
> Warning: Multiple files use the same module name:
>          * Paths_aug found at the following paths
>            * C:\Users\Michael
> Turner\aug\.stack-work\dist\e626a42b\build\aug-exe\autogen\Paths_aug.hs
> (aug:exe:aug-exe)
>            * C:\Users\Michael
> Turner\aug\.stack-work\dist\e626a42b\build\autogen\Paths_aug.hs
> (aug:lib)
> * * * * * * * *
>
> GHCi, version 8.6.5: http://www.haskell.org/ghc/  :? for help
> <command line>: cannot satisfy -package debug
>     (use -v for more information)
>
>
> Regards,
> Michael Turner
> Executive Director
> Project Persephone
> 1-25-33 Takadanobaba
> Shinjuku-ku Tokyo 169-0075
> Mobile: +81 (90) 5203-8682
> turner at projectpersephone.org
>
> Understand - http://www.projectpersephone.org/
> Join - http://www.facebook.com/groups/ProjectPersephone/
> Donate - http://www.patreon.com/ProjectPersephone
> Volunteer - https://github.com/ProjectPersephone
>
> "Love does not consist in gazing at each other, but in looking outward
> together in the same direction." -- Antoine de Saint-Exupéry
>
>
> ------------------------------
>
> Message: 2
> Date: Wed, 19 May 2021 14:34:28 +0200
> From: Francesco Ariis <fa-ml at ariis.it>
> To: beginners at haskell.org
> Subject: Re: [Haskell-beginners] Getting debugging going in ghci -- is
>         there no mercy?
> Message-ID: <20210519123428.GA29827 at extensa>
> Content-Type: text/plain; charset=utf-8
>
> Il 19 maggio 2021 alle 21:10 Michael Turner ha scritto:
> > According to the Haskell wiki, "The trace function is located in the
> > base package", which encouraged me to think it should just work by
> > starting ghci. No such luck. So then I tried "stack gchi --package
> > debug". No such luck. I added packages to stack.yaml as suggested. And
> > here's where I am now.
>
>     λ> :m +Debug.Trace
>     λ> :t +d trace "prova" 234
>     trace "prova" 234 :: Integer
>     λ> trace "prova" 234
>     prova
>     234
>
> `debug` is an — excellent! — debug package by Neil Mitchell, but
> not related to `Debug.Trace`.
>
>
>
> ------------------------------
>
> Subject: Digest Footer
>
> _______________________________________________
> Beginners mailing list
> Beginners at haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
>
>
> ------------------------------
>
> End of Beginners Digest, Vol 154, Issue 9
> *****************************************


More information about the Beginners mailing list