BernardK

BernardK

Programming Ruby 3.2 (5th Edition): B1.0 page 240, short option with/without space

@noelrappin

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

noelrappin

Author of Modern Front-End Development for Rails

Interesting, I must have misinterpreted the documentation. Thanks!

Where Next?

Popular Pragmatic Bookshelf topics Top

jamis
The following is cross-posted from the original Ray Tracer Challenge forum, from a post by garfieldnate. I’m cross-posting it so that the...
New
simonpeter
When I try the command to create a pair of migration files I get an error. user=> (create-migration "guestbook") Execution error (Ill...
New
mikecargal
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...
New
HarryDeveloper
Hi @venkats, It has been mentioned in the description of ‘Supervisory Job’ title that 2 things as mentioned below result in the same eff...
New
Chrichton
Dear Sophie. I tried to do the “Authorization” exercise and have two questions: When trying to plug in an email-service, I found the ...
New
nicoatridge
Hi, I have just acquired Michael Fazio’s “Kotlin and Android Development” to learn about game programming for Android. I have a game in p...
New
jwandekoken
Book: Programming Phoenix LiveView, page 142 (157/378), file lib/pento_web/live/product_live/form_component.ex, in the function below: d...
New
EdBorn
Title: Agile Web Development with Rails 7: (page 70) I am running windows 11 pro with rails 7.0.3 and ruby 3.1.2p20 (2022-04-12 revision...
New
New
dachristenson
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

Other popular topics Top

PragmaticBookshelf
Free and open source software is the default choice for the technologies that run our world, and it’s built and maintained by people like...
New
dasdom
No chair. I have a standing desk. This post was split into a dedicated thread from our thread about chairs :slight_smile:
New
PragmaticBookshelf
Design and develop sophisticated 2D games that are as much fun to make as they are to play. From particle effects and pathfinding to soci...
New
AstonJ
Curious to know which languages and frameworks you’re all thinking about learning next :upside_down_face: Perhaps if there’s enough peop...
New
PragmaticBookshelf
Use WebRTC to build web applications that stream media and data in real time directly from one user to another, all in the browser. ...
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
PragmaticBookshelf
Author Spotlight Jamis Buck @jamis This month, we have the pleasure of spotlighting author Jamis Buck, who has written Mazes for Prog...
New
New
PragmaticBookshelf
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
New
Fl4m3Ph03n1x
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...
New

Sub Categories: