PragProg Customers

Web Development with Clojure, Third Edition: Use of `var` (page 34)

Foxtur

Foxtur

Web Development with Clojure, Third Edition: Use of `var` (page 34)

Hi,

during reading of Chapter 2 I somehow got a little bit confused in regards to the note given at the end of the page which states:

“Note that we have to create a var from the handler in order for this middleware to work”

Given that I’m a beginner Clojure developer this information alone didn’t make too much sense to me until I found the following post on StackOverflow: https://stackoverflow.com/questions/39550513/when-to-use-a-var-instead-of-a-function which is similar to the same paragraph from the book.

So maybe clarification of the why or links to suggested further reading on the topic could spare the readers some time searching the web.

1 comment
/book-web-development-with-clojure-third-edition#suggestion
3 557 1

Marked As Solved

svmbrown

svmbrown

Author of Web Development with Clojure

Thanks for the note! We’ve re-worded our paragraph and added footnotes linking to clojure documentation on vars and evaluation. Will be included in the next beta release.

2
Post #2

Where Next?

View thread on forum
View Web Development With Clojure Third Edition'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
/book-web-development-with-clojure-third-edition#suggestion
3 557 1
Last post

Popular Pragmatic Bookshelf topics Top

jeffmcompsci
PragProg Customers

Design and Build Great Web APIs: typo (page, 19, third bullet in URL list)
Title: Design and Build Great Web APIs - typo “https://company-atk.herokuapp.com/2258ie4t68jv” (page 19, third bullet in URL list) Typo:...
#pragprog#errata/book-design-and-build-great-web-apis
8 1941 7
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
cro
PragProg Customers

Programming Phoenix LiveView: P27, live_path confusion
I am working on the “Your Turn” for chapter one and building out the restart button talked about on page 27. It recommends looking into ...
#question/book-programming-phoenix-liveview
7 3505 14
New
jskubick
PragProg Customers

Kotlin and Android Development featuring Jetpack: $kotlin_version ? (page 8)
I’m running Android Studio “Arctic Fox” 2020.3.1 Patch 2, and I’m embarrassed to admit that I only made it to page 8 before running into ...
#errata/book-kotlin-and-android-development-featuring-jetpack
0 1698 3
New
oaklandgit
PragProg Customers

Hands-on Rust: Failed to Load Texture error (page 121)
Hi, I completed chapter 6 but am getting the following error when running: thread 'main' panicked at 'Failed to load texture: IoError(O...
/book-hands-on-rust
2 1310 3
New
taguniversalmachine
PragProg Customers

Real-Time Phoenix: ProductChannelTest - undefined function describe/2 (pg 203)
Hi, I am getting an error I cannot figure out on my test. I have what I think is the exact code from the book, other than I changed “us...
#question/book-real-time-phoenix
0 1775 6
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
rainforest
PragProg Customers

Real-Time Phoenix: use PubSub with implementation of Phoenix.Socket.Transport rather than channels (page 37)
Hi, I’ve got a question about the implementation of PubSub when using a Phoenix.Socket.Transport behaviour rather than channels. Before ...
#question/book-real-time-phoenix#websockets#phoenixsocket#pubsub
0 1528 3
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

Other popular topics Top

PragmaticBookshelf
Backend>Learning Resources

Web Development with Clojure, Third Edition
Stop developing web apps with yesterday’s tools. Today, developers are increasingly adopting Clojure as a web-development platform. See f...
pragprog.com
#pragprog#web-development/clojure#published-book/book-web-development-with-clojure-third-edition
5 4584 1
New
AstonJ
General Dev>Dev Chat

How fast do you type? Check your WPM here!
Do the test and post your score :nerd_face: :keyboard: If possible, please add info such as the keyboard you’re using, the layout (Qw...
typing-speed-test.aoeu.eu
/keyboards
82 7682 31
New
PragmaticBookshelf
Frontend>Learning Resources

Modern CSS with Tailwind
Tailwind CSS is an exciting new CSS framework that allows you to design your site by composing simple utility classes to create complex e...
pragprog.com
#pragprog/tailwind#published-book/book-modern-css-with-tailwind
12 5813 4
New
Margaret
General Dev>Dev Chat

PragProg’s Medium Posts
Hello everyone! This thread is to tell you about what authors from The Pragmatic Bookshelf are writing on Medium.
#pragprog#blog-post
1147 29994 760
New
foxtrottwist
General Dev>Dev Chat

Warp—The blazingly fast, Rust-based terminal
A few weeks ago I started using Warp a terminal written in rust. Though in it’s current state of development there are a few caveats (tab...
/rust#terminal
52 6785 22
New
DevotionGeo
General Dev>Questions

Do you prefer regular mechanical keyboards or low profile mechanical keyboards and why?
I have always used antique keyboards like Cherry MX 1800 or Cherry MX 8100 and almost always have modified the switches in some way, like...
/keyboards#mechanical-keyboards
27 5496 10
New
PragmaticBookshelf
Backend>Learning Resources

Ash Framework
Explore the power of Ash Framework by modeling and building the domain for a real-world web application. Rebecca Le @sevenseacat and ...
pragprog.com
#pragprog/elixir#published-book/ash/book-ash-framework
15 7555 9
New
PragmaticBookshelf
Backend>Learning Resources

Kotlin Coroutine Confidence
Escape callback hell and ship fast, clean code that reads as smoothly as it runs. Squash bugs and stamp out memory leaks with an intuitiv...
pragprog.com
#pragprog/java/kotlin#published-book/book-kotlin-coroutine-confidence
14 3688 10
New
pragdave
AI>Learning Resources

A Common-Sense Guide to AI Engineering
Build robust LLM-powered apps, chatbots, and agents while mastering AI engineering principles that will help you outlast the tools and th...
pragprog.com
#pragprog
17 1852 8
New
PragmaticBookshelf
Backend>Learning Resources

Eloquent Ruby, Second Edition
Write elegant Ruby code—not just correct, but idiomatic. Go beyond the vocabulary and syntax and learn to express yourself with eloquence...
pragprog.com
#pragprog/ruby#published-book/book-eloquent-ruby-second-edition
11 7668 8
New
Back to top

Latest in Web Development with Clojure, Third Edition

Web Development with Clojure, Third Edition 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