Let's Write Some Bad Ruby

I can't recommend this enough. I was afraid of the shell even having used it quite a lot, preferring to do my changes (like these) with an IDE, and later Perl.

How about a nice game of golf?

    find app/views/foo -depth -type f | while read f; do mkdir -p $(dirname ${f##foo/}); sed "${f##foo/}" -e s'/\([a-z]*\)foo_\([a-z]*\)path/\1\2path/g'; echo rm "$f"; done

As the author I thought I'd comment:

I wrote this article, because when I was a very new developer, I was learning a lot more Rails than I was Ruby. It had never occurred to me to use Ruby for scripting until I paired with a well rounded Rubyist. With the influx of people learning Rails, I've talked to many people who know much less about Ruby than I did when I was starting out. This isn't mentioned in the article at all, but it was definitely something I thought about when I decided to write it. Honestly, if this helps push one new dev to go out and decided to actually learn some extra Ruby outside of Rails, I'll be happy.

I agree 100% about the shell comments. I know enough shell to do my job, but for me it's quicker to write a Ruby script. Not saying it's the most efficient way, but it is a way, and it's more efficient than doing it by hand. As much as I'd love to be a unix shell wizard, I'd rather be improving my Javascript, or learning more Elixir.

As for the namespace vs scope: The example was just a way to end up with a scenario where we needed to change some text. Plus, for clarity, if I don't want my controllers or URL namespaced, my routes and files should reflect that, not work around it with a scope unless necessary for some reason(in my opinion). I actually later thought that I should've used the script on a JS project, just to help highlight the fact that this is totally independent of Rails.

I don't do this anymore. I learnt how to use bash, sed, grep, awk, netcat, socat, and as a user, I work in terminals. I accumulated a lot of scripts, to the point where they were the first set of tools I would reach.

But it becomes a self-renforcing loop: the more you rely on this toolbox, the more problems you create that are best solved with the same tools and the particular mindset they promote. But for work-related tasks, throwaway code rarely is: your code becomes part of your infrastructure and you have to make it work reliably now and later.

After some years, things are not so fun anymore: assembling strings means escaping/quoting characters for different formats and languages. With shell scripts, the path of least resistance is unsafe and introduce many unneeded assumptions.

For example, in the above code, globbing in app/views/foo/... in the "for" expression will not work if you have spaces in file names. And if you can get it right, $file is not inside double-quotes; mv will erase any previously existing file. And even though some of the assumptions are valid in context, will they always hold?

In order to make them hold, people tend to adapt their problem to fit their tools, not the other way: file names are always in a well-known ascii range, with no space but a specific separator and zero-padding (e.g. myfile_00020, because files are sorted lexicographically). Unless you are willing to use json/xml tools, data is cut into pieces of strings: records are line-separated; each field is colon-separated, each subfield is comma-separated, etc (recursive CSV). And one day, that field which always contain dates in YY/DD/MM format (why not ISO-8601?) starts having a time too, formatted HH:MM. After a painful recovery of trashed data, you add "just one more script" to properly escape colons.

Languages are designed with specific goals in mind and writing complex programs is not what scripting languages are optimized for. I now prefer to use language with data-structures, functions, objects, namespaces: less use for strings and regexes. If I try to write onto an existing file, I will be warned (or I can explicitely allow overwriting). Paths are organized as os-independant trees, etc: there are better interfaces to the facility provided by the OS. Coincidently, the need for scripts gradually reduced, at least the one I need to save (I still chain programs on the command-line).

Globing works fine with spaces, but you need to quote variables, e.g. $file -> "$file", to avoid parsing of their content by bash. See Bash-FAQ for details.

Problem with shell is that you need to solve same problems again and again. This is why I wrote "bash-modules" script (https://github.com/vlisivka/bash-modules), which allows to write module with common code and then just do ". import.sh module" from script or command line.