Being able to call external commands with backticks alone makes it better suited than Python for shell scripting.
Ruby: A great language for shell scripts
111–120 of 368 posts
Re: Ruby: A great language for shell scripts
#112Overall a nice lite write up! Bash is great, but it occasionally becomes untenable, usually around the time where HTTP and whatnot becomes involved. Same goes for shell exec exit codes, you can use an API like popen3 for this: https://ruby-doc.org/stdlib-2.4.1/libdoc/open3/rdoc/Open3.ht...
You mention using threads and regex match global variables in the same write up. Please use the regex match method response instead of the $1 variables to save yourself the potential awful debugging session. It even lets you access named capture groups in the match response using the already familiar Hash access API. Example: https://stackoverflow.com/a/18825787
In general, just don’t use global variables in Ruby. It’s already SO easy to move “but it has to be global” functionality to static class methods or constants that I’ve encountered exactly zero cases where I have NEEDED global variables. Even if you need a “stateful constant” Ruby had a very convenient Singleton mixin that provides for a quick and easy solution.
Besides, if you actually WERE to take advantage of them being global VARIABLES (reassigning the value) I would confidently bet that your downstream code would break, because I’m guessing said downstream code assumes the global value is constant. Just avoid them, there’s no point, use constants. This applies to any language TBH, but here we’re talking about Ruby :)
Re: Ruby: A great language for shell scripts
#113Earlier quoted context omitted.
> ... maybe extract those files to required files, add gems, whatever. CPAN is the killer feature of Perl. It just works. First off, most of the time I don't need a CPAN module for doing shell scripting in perl. Perl itself is rich enough with the file manipulations that are needed for any script of less than 100 lines. My experiences with Ruby and installing gems have been less pleasant. Different implementations of…
Does anyone under age 50 or so even know Perl?
Yes.
Re: Ruby: A great language for shell scripts
#114I sometimes wonder why we don't see ruby used for shell stuff more often. It inherited most of the good stuff for shell scripting from Perl, and Perl took a lot of it's syntax from sh and sed and awk, so almost anything you can do in shell script you can do in ruby, but with an option of making it gradually less terse and more readable, while having sane variables and data handling from the start. Also ruby is great…
> I sometimes wonder why we don't see ruby used for shell stuff more often. The reason we don't see Ruby used more for shell stuff is because Python won this particular war. It's already installed on basically every Linux distribution out there, and this simple fact outweighs all other language considerations for probably >95% of people who are writing shell scripts in something that isn't Bash. Personally, I don't m…
How hard is to install it though? That doesn't sound like a reason not to use it.
Re: Ruby: A great language for shell scripts
#115Earlier quoted context omitted.
It's been a while since I reinstalled Ubuntu, but the latest version (24.04 LTS) definitely includes Ruby (3.2) according to their docs [0]. [0] https://canonical.com/blog/canonical-releases-ubuntu-24-04-n... .
It's in the repos, but not installed by default. Not on my Fedora box either.
And Python 3 is everywhere
Re: Ruby: A great language for shell scripts
#116The greatest feature for this is inline deps, something very rare to have built-in (I've only found Deno to have a similar feature): https://bundler.io/guides/bundler_in_a_single_file_ruby_scri...
Elixir also has inline dependencies in scripts, via `Mix.install`: https://hexdocs.pm/mix/1.17.1/Mix.html#install/2. I've used it quite a bit, it works great.
Re: Ruby: A great language for shell scripts
#117Earlier quoted context omitted.
> I sometimes wonder why we don't see ruby used for shell stuff more often. The reason we don't see Ruby used more for shell stuff is because Python won this particular war. It's already installed on basically every Linux distribution out there, and this simple fact outweighs all other language considerations for probably >95% of people who are writing shell scripts in something that isn't Bash. Personally, I don't m…
How hard is to install it though? That doesn't sound like a reason not to use it.
Mitigating the risk of downloading a script from the internet and executing it
-- even from a "trusted" website or package manager -- is absolutely a good reason not to use it.
Re: Ruby: A great language for shell scripts
#118I sometimes wonder why we don't see ruby used for shell stuff more often. It inherited most of the good stuff for shell scripting from Perl, and Perl took a lot of it's syntax from sh and sed and awk, so almost anything you can do in shell script you can do in ruby, but with an option of making it gradually less terse and more readable, while having sane variables and data handling from the start. Also ruby is great…
> I sometimes wonder why we don't see ruby used for shell stuff more often. The reason we don't see Ruby used more for shell stuff is because Python won this particular war. It's already installed on basically every Linux distribution out there, and this simple fact outweighs all other language considerations for probably >95% of people who are writing shell scripts in something that isn't Bash. Personally, I don't m…
this whole argument is silly. In my time on this site, I have seen someone suggest that every language is good for shell scripting including C.
Python and bash are used in the real world most often because convincing your sysadmin/infra/boss guy to install ruby for one script is a hard sell when you already have good-enough tools built into the system that don't add risk/complexity.
Re: Ruby: A great language for shell scripts
#119It seems like a waste of precious syntax to dedicate backticks to running shell commands. What's between the backticks is not even portable; the commands rely on an operating-system-specific command interpreter. > puts `ls`.lines.map { |name| name.strip.length } # prints the lengths of the filenames Fantastic example, except for the commandment violation: "thou shalt not parse the output of 'ls'"! You really want to…
They have inherited the second biggest mistake of shellscripts; Requiring the user to manually check $? after each command.
No thanks. Anything that doesn't have error handling enabled by default goes straight in the trash bin.
Re: Ruby: A great language for shell scripts
#120Earlier quoted context omitted.
> I sometimes wonder why we don't see ruby used for shell stuff more often. The reason we don't see Ruby used more for shell stuff is because Python won this particular war. It's already installed on basically every Linux distribution out there, and this simple fact outweighs all other language considerations for probably >95% of people who are writing shell scripts in something that isn't Bash. Personally, I don't m…
How hard is to install it though? That doesn't sound like a reason not to use it.
Significantly harder than doing nothing