How to add trailing slash if needed with gsub

Question

I'm trying to add trailing slash if needed:

a = '/var/www'
a.gsub
...

I don't know how to do it.

Answer 1

a = File.join(a, "")

Swift, simple, and has the effect of guaranteeing that a ends in a path separator; that is, it gives the same result whether a is "/var/www" or "/var/www/".

This is same as Joe White's comment above; I don't know why he didn't submit it as an answer, as it deserves to be one.

Oddly, the Pathname library doesn't provide a convenient way of doing the same thing.

Answer 2

Here's a bit more readable version

path << '/' unless path.end_with?('/')

Answer 3

Why do you want to use gsub?

1. You're not doing substitution (nothing is to be removed from the string)
2. If you're substituting, and only need it done in one place, use sub not gsub.
3. If you're substituting, and want to modify the string, use sub! or gsub!.

Since you're not doing substitution, just append the slash if needed:

path << '/' if path[-1] != '/' # Make sure path ends with a slash

Update: To make it compatible with older versions of Ruby (1.8.x), modify it slightly:

path << '/' if path[-1].chr != '/' # Make sure path ends with a slash

Answer 4

You can use .chomp('/') to strip of the optionally trailing / and then .concat('/') to append a slash again.

'/var/www/'.chomp('/').concat('/')   # => "/var/www/"
'/var/www'.chomp('/').concat('/')    # => "/var/www/"