PragProg Customers

From Ruby to Elixir:

yba

yba

From Ruby to Elixir:

@sb8244

From Ruby to Elixir -
iex(1)> Enum.reduce([1, 2, 3], 0, fn num, ac → if num > max, do: num, else: ac end)
error: undefined variable “max”
└─ iex:6
** (CompileError) cannot compile code (errors have been logged)
command not working (page 42)

1 comment
#errata/book-from-ruby-to-elixir
1 234 1

First Post!

sb8244

sb8244

Author of From Ruby to Elixir and Real-Time Phoenix

Oof, thanks for this! I will make sure it’s fixed (and have an action item to go through every code entry in book to make sure it works properly.)

If it’s not clear, the ac variable should be called max here. I originally called it accumulator, but I find max easier to understand as that represents the purpose of the accumulation.

Post #2

Where Next?

View thread on forum
View From Ruby To Elixir'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-from-ruby-to-elixir
1 234 1
Last post

Popular Pragmatic Bookshelf topics Top

iPaul
PragProg Customers

The Definitive ANTLR 4 Reference: Program deprecation warning
page 37 ANTLRInputStream input = new ANTLRInputStream(is); as of ANTLR 4 .8 should be: CharStream stream = CharStreams.fromStream(i...
#errata/book-the-definitive-antlr-4-reference
4 986 0
New
jdufour
PragProg Customers

The Cucumber for Java Book:
Hello! On page xix of the preface, it says there is a community forum "… for help if your’re stuck on one of the exercises in this book… ...
#question/book-the-cucumber-for-java-book
3 1142 1
New
mikecargal
PragProg Customers

Hands-on Rust: question about get_component
Title: Hands-on Rust: question about get_component (page 295) (feel free to respond. “You dug you’re own hole… good luck”) I have somet...
#question/book-hands-on-rust
1 1163 5
New
adamwoolhether
PragProg Customers

Distributed Services with Go: receiving Unknown flag: --go_opt when compiling protobuf (page 20)
When trying to generate the protobuf .go file, I receive this error: Unknown flag: --go_opt libprotoc 3.12.3 MacOS 11.3.1 Googling ...
/book-distributed-services-with-go
0 4908 3
New
curtosis
PragProg Customers

Build a Weather Station with Elixir and Nerves: 'mix deps.get' does not work if user has not created a keyfile (page 16)
Running mix deps.get in the sensor_hub directory fails with the following error: ** (Mix) No SSH public keys found in ~/.ssh. An ssh aut...
#errata/book-build-a-weather-station-with-elixir-and-nerves
2 1449 3
New
jskubick
PragProg Customers

Kotlin and Android Development featuring Jetpack: SwitchCompat's thumbTint and trackTint being ignored (page 76)
I think I might have found a problem involving SwitchCompat, thumbTint, and trackTint. As entered, the SwitchCompat changes color to hol...
#errata/book-kotlin-and-android-development-featuring-jetpack
0 2702 2
New
adamwoolhether
PragProg Customers

Powerful Command-Line Applications in Go: Exercise Solutions (many pages)
Is there any place where we can discuss the solutions to some of the exercises? I can figure most of them out, but am having trouble with...
#question/book-powerful-command-line-applications-in-go
17 1377 9
New
taguniversalmachine
PragProg Customers

Programming Phoenix LiveView: B6.0 pg 56 - current-user not set
It seems the second code snippet is missing the code to set the current_user: current_user: Accounts.get_user_by_session_token(session["...
#errata/book-programming-phoenix-liveview
0 1898 8
New
jwandekoken
PragProg Customers

Programming Phoenix LiveView: Live Upload Match Error
Book: Programming Phoenix LiveView, page 142 (157/378), file lib/pento_web/live/product_live/form_component.ex, in the function below: d...
#errata/book-programming-phoenix-liveview
7 1154 10
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 2120 6
New

Other popular topics Top

AstonJ
General Dev>Dev Chat

What are you listening to?
A thread that every forum needs! Simply post a link to a track on YouTube (or SoundCloud or Vimeo amongst others!) on a separate line an...
#community#music
202 4935 102
New
AstonJ
General Dev>Hardware

Poll: Which keyboard layout do you use?
poll poll Be sure to check out @Dusty’s article posted here: An Introduction to Alternative Keyboard Layouts It’s one of the best write-...
colemakmods.github.io
#polls/keyboards
10 5701 11
New
AstonJ
General Dev>Hardware

Seen any cool new keyboards?
We have a thread about the keyboards we have, but what about nice keyboards we come across that we want? If you have seen any that look n...
/keyboards#mechanical-keyboards
49 5587 39
New
AstonJ
General Dev>Hardware

Keyboard thock (sound)
I’ve been hearing quite a lot of comments relating to the sound of a keyboard, with one of the most desirable of these called ‘thock’, he...
/keyboards#mechanical-keyboards
14 9747 8
New
DevotionGeo
General Dev>Dev Chat

The V Programming Language
The V Programming Language Simple language for building maintainable programs V is already mentioned couple of times in the forum, but I...
#programminguages/v
21 12589 7
New
AstonJ
Data Science

Can AI/ML predict a lottery win?
Biggest jackpot ever apparently! :upside_down_face: I don’t (usually) gamble/play the lottery, but working on a program to predict the...
#ai#machine-learning
19 3496 10
New
PragmaticBookshelf
Community>In The Spotlight

Spotlight: Dmitry Zinoviev (Author) Interview and AMA!
Author Spotlight Dmitry Zinoviev @aqsaqal Today we’re putting our spotlight on Dmitry Zinoviev, author of Data Science Essentials in ...
#author-spotlight/python/book-complex-network-analysis-in-python/book-data-science-essentials-in-python/book-resourceful-code-reuse/book-pythonic-programming
33 5041 14
New
PragmaticBookshelf
Backend>Learning Resources

Programming Ruby 3.2 (5th Edition)
Programming Ruby is the most complete book on Ruby, covering both the language itself and the standard library as well as commonly used t...
twitter.com
#pragprog/ruby/rails#published-book/book-programming-ruby-3-2-5th-edition
28 6382 13
New
CommunityNews
General Dev>In The News

X can’t stop spread of explicit, fake AI Taylor Swift images
Will Swifties’ war on AI fakes spark a deepfake porn reckoning?
arstechnica.com
/swift
0 7404 0
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 7706 10
New
Back to top

Latest in From Ruby to Elixir

From Ruby to Elixir 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!"

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!"

View all our sponsors ❯

We're in Beta

About us Mission Statement See our Roadmap