The Traditional Way
The traditional way to create file paths that are cross platform in Ruby, was to join them up as arguments in a File.join call:
Result:
"./../../config/database.yml"
Now thats all nice and everything but if you want to change it, you would have the inconvenience of having to add or remove commas, or single|double quotes, which can be a bit of a hassle.
Prettying it Up
So how about we pretty it up a little?
Result:
"./../../config/database.yml"
Now doesn’t that look a whole better?
What in the world is %w[...]?
Why does this work just as well?
The %w[...] creates an array of Strings separated by the whitespaces in the list.
Result:
["..", "..", "config", "database.yml"]
But what if you have a space in the file name? Well you can use a backslash as an escape key and presto!
Result:
["..", "..", "config", "a file"]
Note: I’m not so sure what this operator is called, and any help giving it a name would be greatly appreciated.
3 Comments
This snippet is related but not exactly trying to solve the same problem: http://snippets.dzone.com/posts/show/2447.
Hey, I have to say great blog! I also read your story about how you got started with OSS and your programming career. I can completely relate!
Anyway… I’m not sure of the operator name either, but recently I was re-writing Dr Nic’s “gitify” script on DZone snippets and I made great use of %{ }. I used %{ } to build my strings into a Ruby one-liner that was converted into a shell command alias. I had to watch my single and double quotes usage, since I was fitting this Ruby into an alias definition (code was already within double/single quotes)…
http://snippets.dzone.com/posts/show/4813
BTW: Add our blog to your reader, and keep up the great posts!
Usually you also want File.expand_path, to avoid multiple requires and such.