BernardK
Programming Ruby 3.2 (5th Edition): B1.0 page 240, short option with/without space
page 240, last paragraph, lines 5-7 : the short option can have a space
… … … … … … … … … … … … … … … … … … … … … There’s one slight bit of weirdness here, which is
that a required argument is separated from a long option by a space but is flush against a
short option, so -xTHING
From the doc and experimentation, the marker can be separated by a space from the short option (it MUST be separated from a long option).
parser.on('-x XXX' … or parser.on('-xXXX' … have the same effect.
require "optparse"
parser = OptionParser.new
parser.on('-x XXX', '--xxx', 'Required argument via short name') do |value|
puts "option -x is '-x XXX'"
end
parser.on('-zZZZ', '--zzz', 'Required argument via short name') do |value|
puts "option -z is '-zZZZ'"
end
parser.parse!
% ruby -w rubyworld/option_doc.rb --help
Usage: option_doc [options]
-x, --xxx XXX Required argument via short name
-z, --zzzZZZ Required argument via short name
% ruby -w rubyworld/option_doc.rb -x x
option -x is '-x XXX'
% ruby -w rubyworld/option_doc.rb -z x
option -z is '-zZZZ'
First Post!
noelrappin
Author of Modern Front-End Development for Rails
Interesting, I must have misinterpreted the documentation. Thanks!
Popular Pragmatic Bookshelf topics
This test is broken right out of the box…
— FAIL: TestAgent (7.82s)
agent_test.go:77:
Error Trace: agent_test.go:77
agent_test.go:...
New
page 37
ANTLRInputStream input = new ANTLRInputStream(is);
as of ANTLR 4 .8 should be:
CharStream stream = CharStreams.fromStream(i...
New
Hi everyone!
There is an error on the page 71 in the book “Programming machine learning from coding to depp learning” P. Perrotta. You c...
New
Title: Web Development with Clojure, Third Edition - migrations/create not working: p159
When I execute the command:
user=> (create-...
New
Hi! I know not the intentions behind this narrative when called, on page XI:
mount() |> handle_event() |> render()
but the correc...
New
#book-python-testing-with-pytest-second-edition
Hi. Thanks for writing the book. I am just learning so this might just of been an issue ...
New
The markup used to display the uploaded image results in a Phoenix.LiveView.HTMLTokenizer.ParseError error.
lib/pento_web/live/product_l...
New
root_layout: {PentoWeb.LayoutView, :root},
This results in the following following error:
no “root” html template defined for PentoWeb...
New
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...
New
Is there any plan for volume 2? :slight_smile:
New
Other popular topics
Write Elixir tests that you can be proud of. Dive into Elixir’s test philosophy and gain mastery over the terminology and concepts that u...
New
New
I’m thinking of buying a monitor that I can rotate to use as a vertical monitor?
Also, I want to know if someone is using it for program...
New
Bought the Moonlander mechanical keyboard. Cherry Brown MX switches. Arms and wrists have been hurting enough that it’s time I did someth...
New
New
Tailwind CSS is an exciting new CSS framework that allows you to design your site by composing simple utility classes to create complex e...
New
The V Programming Language
Simple language for building maintainable programs
V is already mentioned couple of times in the forum, but I...
New
Author Spotlight
Erin Dees
@undees
Welcome to our new author spotlight! We had the pleasure of chatting with Erin Dees, co-author of ...
New
Author Spotlight:
Peter Ullrich
@PJUllrich
Data is at the core of every business, but it is useless if nobody can access and analyze ...
New
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...
New
Categories:
Sub Categories:
Popular Portals
- /elixir
- /rust
- /wasm
- /ruby
- /erlang
- /phoenix
- /keyboards
- /python
- /js
- /rails
- /security
- /go
- /swift
- /vim
- /clojure
- /java
- /emacs
- /haskell
- /svelte
- /onivim
- /typescript
- /kotlin
- /c-plus-plus
- /crystal
- /tailwind
- /react
- /gleam
- /ocaml
- /elm
- /flutter
- /vscode
- /ash
- /html
- /opensuse
- /zig
- /centos
- /deepseek
- /php
- /scala
- /react-native
- /lisp
- /textmate
- /sublime-text
- /nixos
- /debian
- /agda
- /django
- /deno
- /kubuntu
- /arch-linux
- /nodejs
- /revery
- /ubuntu
- /spring
- /manjaro
- /lua
- /diversity
- /julia
- /markdown
- /slackware









