[ruby-talk:02897] Funny unexpected match....

Put simply, using "||" as a match expression in gsub matches an empty line.  Say WHAT?  I want to match a literal "vertical-bar vertical-bar".

Here's the test code:

#!/opt/ruby/bin/ruby

# ruby 1.4.3 (1999-12-08) [hppa1.1-hpux10.20]

test = "||"
test2 = "\|\|"
line = ""

p line.gsub(/#{test}/, "*** ding ding ding ***")
p line.gsub(/#{test2}/, "*** dong dong dong ***")

To me, this should print

nil
nil

But the output instead is:

*** ding ding ding ***
*** dong dong dong ***

Why?

PS: This code came up in a pretty printer I'm writing - not a "reformatter" but an HTML-based "pretty-printer" which highlights different sections and so on.  If you've read "Code Complete" you've seen something like it.  If you haven't read "Code Complete", YOU SHOULD (as well as any programmers working for you, or any programmers you work for, or any programmers you know...... :-)