PragProg Customers

Effective Haskell: p97 P1.0 Error message is not correct

lkuty

lkuty

Effective Haskell: p97 P1.0 Error message is not correct

In the code sample at the top of the page, the error message No instance for (Data.String.IsString Int) is not correct and should be the same as the one seen in the main text which is Couldn’t match expected type ‘Int’ with actual type ‘[Char]’.

View thread on forum
#errata/book-effective-haskell
0 1 0

Where Next?

View thread on forum
View Effective Haskell's book portal
Post errata for this book
Post a suggestion for this book
Post a question about this book
Post a review about this book
Home PragProg Customers
#errata/book-effective-haskell
0 1 0
Last post

Popular Pragmatic Bookshelf topics Top

brianokken
PragProg Customers

Python Testing with pytest: pytest now requires markers to be declared (downloadable code)
Many tasks_proj/tests directories exist in chapters 2, 3, 5 that have tests that use the custom markers smoke and get, which are not decl...
#errata/book-python-testing-with-pytest
2 1383 2
New
simonpeter
PragProg Customers

Web Development with Clojure, Third Edition: (create-migration "guestbook") not working (page 9)
When I try the command to create a pair of migration files I get an error. user=> (create-migration "guestbook") Execution error (Ill...
#errata/book-web-development-with-clojure-third-edition
5 1788 4
New
herminiotorres
PragProg Customers

Programming Phoenix LiveView: Typo
Hi! I know not the intentions behind this narrative when called, on page XI: mount() |> handle_event() |> render() but the correc...
#errata/book-programming-phoenix-liveview
3 1307 17
New
leba0495
PragProg Customers

A Common-Sense Guide to Data Structures and Algorithms, Second Edition: (pg460)
Hello! Thanks for the great book. I was attempting the Trie (chap 17) exercises and for number 4 the solution provided for the autocorre...
#errata/book-a-common-sense-guide-to-data-structures-and-algorithms-second-edition
0 1157 3
New
kevinjyh
PragProg Customers

Python Testing with pytest, Second Edition:Abou epub format
Is the book’s epub format available to read on Google Play Books?
#question/book-python-testing-with-pytest-second-edition
0 1126 3
New
jonmac
PragProg Customers

Kotlin and Android Development featuring Jetpack: allprojects should be moved to settings.gradle (page 245)
The allprojects block listed on page 245 produces the following error when syncing gradle: “org.gradle.api.GradleScriptException: A prob...
#suggestion/book-kotlin-and-android-development-featuring-jetpack
1 2304 1
New
kolossal
PragProg Customers

Hands on Rust: Need help with error - thread 'main' panicked at 'Failed to load texture
Hi, I need some help, I’m new to rust and was learning through your book. but I got stuck at the last stage of distribution. Whenever I t...
#question/book-hands-on-rust
3 1989 5
New
mert
PragProg Customers

Agile Web Development with Rails 7: page 152, page 153:
AWDWR 7, page 152, page 153: Hello everyone, I’m a little bit lost on the hotwire part. I didn’t fully understand it. On page 152 @rub...
#question/book-agile-web-development-with-rails-7
0 1230 4
New
NaplesDave
PragProg Customers

PragProg Customers Kotlin and Android Development: pg. 8 Build Gradle error: Could not get unknown property 'kotlin_version'
I am using Android Studio Chipmunk | 2021.2.1 Patch 2 Build #AI-212.5712.43.2112.8815526, built on July 10, 2022 Runtime version: 11.0....
#question/book-kotlin-and-android-development-featuring-jetpack
0 1456 2
New
dachristenson
PragProg Customers

Kotlin and Android Development featuring Jetpack: No activity_main.xml anymore
I just bought this book to learn about Android development, and I’m already running into a major issue in Ch. 1, p. 20: “Update activity...
#errata/book-kotlin-and-android-development-featuring-jetpack
0 2172 6
New

Other popular topics Top

PragmaticBookshelf
Backend>Learning Resources

Programming Machine Learning
Machine learning can be intimidating, with its reliance on math and algorithms that most programmers don't encounter in their regular wor...
pragprog.com
#pragprog#ai/python#published-book/book-programming-machine-learning#math#algorithms
6 5350 3
New
PragmaticBookshelf
Game Dev>Learning Resources

The Ray Tracer Challenge
Brace yourself for a fun challenge: build a photorealistic 3D renderer from scratch! In just a couple of weeks, build a ray tracer that r...
pragprog.com
#pragprog#published-book/book-the-ray-tracer-challenge#algorithms
3 6115 0
New
PragmaticBookshelf
General Dev>Learning Resources

Seven More Languages in Seven Weeks
Learn from the award-winning programming series that inspired the Elixir language, and go on a step-by-step journey through the most impo...
pragprog.com
#pragprog/elixir/julia/lua#published-book#factor/elm#minikanren/idris/book-seven-more-languages-in-seven-weeks
4 5862 0
New
AstonJ
Science/Tech>Tech Chat

What are you watching?
Or looking forward to? :nerd_face:
#community
503 15149 280
New
PragmaticBookshelf
Backend>Learning Resources

Effective Haskell
Build efficient applications that exploit the unique benefits of a pure functional language, learning from an engineer who uses Haskell t...
pragprog.com
#pragprog/haskell#published-book/book-effective-haskell
15 10218 1
New
AstonJ
Frontend>Chat

Online Hand to eye coordination test
Was just curious to see if any were around, found this one: I got 51/100: Not sure if it was meant to buy I am sure at times the b...
#online-tools
4 4562 1
New
AstonJ
AI>Chat

How to: Run DeepSeek on Mac, Windows, and Linux!
This is a very quick guide, you just need to: Download LM Studio: https://lmstudio.ai/ Click on search Type DeepSeek, then select the o...
#macs/deepseek#guides#lm-studio
14 9328 10
New
Fl4m3Ph03n1x
AI>Questions

What are the best text-to-speech ai generation tools that you can run locally?
Background Lately I am in a quest to find a good quality TTS ai generation tool to run locally in order to create audio for some videos I...
#ai#text-to-speech
6 12337 3
New
PragmaticBookshelf
Backend>Learning Resources

Risk-First Software Development, Second Edition
As digital systems increasingly run the world, mastery of the recurring patterns of software development risk is the key to fast and effe...
pragprog.com
#pragprog#published-book/book-risk-first-software-development-second-edition
12 4217 8
New
xiji2646-netizen
AI>Chat

Claude Code's entire source just leaked (512K lines) - anyone else digging through it?
Woke up to this today: Claude Code’s complete source code exposed via npm source map. Not a snippet. All 512,000 lines. 1,900 TypeScript ...
#claude
6 8359 5
New
Back to top

Latest in Effective Haskell

Effective Haskell Portal ❯

PragProg Customers

Pragmatic Bookshelf PragProg Customers ❯

Latest on Devtalk

Devtalk ❯

We ❤️ helpful members!

We reward our most helpful members via our MOTM scheme - by giving away a whopping 25 books per year!

Member of the Month

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

Linux New Media

Publishing Linux Magazine, ADMIN, and MakerSpace for 25+ years.

View all our sponsors ❯

Categories:

Sub Categories:

Popular Portals

Devtalk Sponsors

Pragmatic Bookshelf

Practical resources that improve the lives of professional developers.

Erlang Solutions

We build trusted fault-tolerant systems that scale to billions of users.

Honeybadger

Real-time error tracking, performance insights, and observability for devs.

EEF

Supporting innovation across the BEAM ecosystem.

coders51

We build reliable cloud platforms for business-critical systems.

Manning Publications

Develop your skills with books, videos, and courses.

AppSignal

Catch errors, track performance, monitor hosts and more.

WyeWorks

Enabling companies to succeed by building software people love.

Pragmatic Studio

Courses that move you from confusion to "Aha, now I get it!"

Linux New Media

Publishing Linux Magazine, ADMIN, and MakerSpace for 25+ years.

View all our sponsors ❯

We're in Beta

About us Mission Statement See our Roadmap