Ruby 1.8.7 RegExp doesn't work with meta-character "\h"

Question

If I run this in a 1.8.7 console:

$ irb-ruby-1.8.7-p330
1.8.7 :001 > "0a" =~ /\h\h/
 => nil

And if I run the same in a 1.9.2 console:

$ irb-ruby-1.9.2-p290
1.9.2p290 :001 > "0a" =~ /\h\h/
 => 0

:/

I've never seen `\h` before. What's it supposed to do? – Ryan Bigg Sep 03 '12 at 17:05 — Ryan Bigg, Sep 03 '12 at 17:05
@RyanBigg http://ruby.runpaint.org/regexps#escapes – fguillen Sep 03 '12 at 17:07 — fguillen, Sep 03 '12 at 17:07

score 1 · Accepted Answer · answered Sep 03 '12 at 17:30

You're right that \h doesn't seem to be recognised by the standard Ruby 1.8.7 regexp library. This can be confirmed using Rubular. If you need 1.8 compatibility in your code without using any additional gems I think your only alternative is to use an equivalent character class [0-9a-fA-F].

Ruby 1.8.7 RegExp doesn't work with meta-character "\h"

1 Answers1