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
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...
New
Working through the steps (checking that the Info,plist matches exactly), run the demo game and what appears is grey but does not fill th...
New
Hi,
build fails on:
bracket-lib = “~0.8.1”
when running on Mac Mini M1 Rust version 1.5.0:
Compiling winit v0.22.2
error[E0308]: mi...
New
Page 28: It implements io.ReaderAt on the store type.
Sorry if it’s a dumb question but was the io.ReaderAt supposed to be io.ReadAt?
...
New
This isn’t directly about the book contents so maybe not the right forum…but in some of the code apps (e.g. turbo/06) it sends a TURBO_ST...
New
I’m not quite sure what’s going on here, but I’m unable to have to containers successfully complete the Readiness/Liveness checks. I’m im...
New
The test is as follows:
Scenario: Intersecting a scaled sphere with a ray
Given r ← ray(point(0, 0, -5), vector(0, 0, 1))
And s ← sphere...
New
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...
New
It seems the second code snippet is missing the code to set the current_user:
current_user: Accounts.get_user_by_session_token(session["...
New
Getting an error when installing the dependencies at the start of this chapter:
could not compile dependency :exla, "mix compile" failed...
New
Other popular topics
Hello Devtalk World!
Please let us know a little about who you are and where you’re from :nerd_face:
New
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...
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
From finance to artificial intelligence, genetic algorithms are a powerful tool with a wide array of applications. But you don't need an ...
New
There’s a whole world of custom keycaps out there that I didn’t know existed!
Check out all of our Keycaps threads here:
https://forum....
New
Biggest jackpot ever apparently! :upside_down_face:
I don’t (usually) gamble/play the lottery, but working on a program to predict the...
New
I am trying to crate a game for the Nintendo switch, I wanted to use Java as I am comfortable with that programming language. Can you use...
New
zig/http.zig at 7cf2cbb33ef34c1d211135f56d30fe23b6cacd42 · ziglang/zig.
General-purpose programming language and toolchain for maintaini...
New
Hello,
I’m a beginner in Android development and I’m facing an issue with my project setup. In my build.gradle.kts file, I have the foll...
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
- /flutter
- /elm
- /vscode
- /ash
- /html
- /opensuse
- /deepseek
- /zig
- /centos
- /php
- /scala
- /react-native
- /lisp
- /sublime-text
- /textmate
- /nixos
- /debian
- /agda
- /deno
- /django
- /kubuntu
- /arch-linux
- /nodejs
- /spring
- /ubuntu
- /revery
- /manjaro
- /diversity
- /julia
- /lua
- /markdown
- /slackware









