Regexp differences between Ruby and ROR [hpricot]

Rails
1

I am trying to get hpricot to work from within rails and ran into this
peculiarity. I had a situation where the script runs fine if run as a
ruby script but bombs if called from within rails (as a method of a
model). After some debugging, it came down to this …

Fire up script\console from the root directory of a rails project -

Loading development environment.

expr = “title”
=> “title”

m = expr.match(/(^[#.]?)([a-z0-9]*)/)
=> #MatchData:0xb78d1370

$’
=> nil

m.post_match
=> “”

$’ and m.post_match are different.

Do the same in irb -
irb(main):001:0> expr = “title”
=> “title”
irb(main):002:0> m = expr.match(/(^[#.]?)([a-z0-9]*)/)
=> #MatchData:0xb7c07b48
irb(main):003:0> $’
=> “”
irb(main):004:0> m.post_match
=> “”

$’ and m.post_match are the same.

Ironically if you test this on windows results are script\console are
identical to those of irb. But for Mac or Ubuntu I see the above
behavior.
Tested with ruby 1.8.4.

questions -

  1. Is this expected behavior?
  2. Can you suggest a workaround ? I would prefer not to touch the gem
    code in hpricot – unless it is the only alternative.
  • Chet
2

Any body run into this?