I posted this in the Ruby On Rails forum a moment ago because of other
URI.escape() related messages there, but really it’s a Ruby thing, not a
Rails thing, so it belongs in the Ruby forum. Thus, a repost 
URI.escape() is supposed to be able to take a second parameter listing
unsafe characters in the URI. This may be a regexp or string. If a
string, it’s supposed to represent a character set listing all unsafe
characters. An example given in the core documentation at:
http://www.ruby-doc.org/stdlib/libdoc/uri/rdoc/classes/URI/Escape.html#M008992
…is:
p URI.escape(“@?@!”, “!?”)
=> “@%3F@%21”
Unfortunately this doesn’t work. It seems that the string does not
represent a character set to match any more, but a literal string to
find - thus the following result is actually seen:
p URI.escape(“@?@!”, “!?”)
=> “@?@!”
p URI.escape(“@?@!”, “@?”)
=> “%40%3F@!”
Matching strings in this way is thoroughly bizarre as highlighted by the
above example; “@” is being escaped for the substring “@?” but not for
the substring “@!”. The way to get the documented style of substitution
is rather clumsy; one must manually construct the character set:
p URI.escape(“@?@!”, Regexp.new(“[!?]”))
=> “@%3F@%21”
I was going to update the documentation Wiki to mention the differing
behaviour in Ruby 1.8.4 by clicking on the link given at the bottom of
the page, which goes to:
http://www.ruby-doc.org/ru/wiki/index.rb/Core/URI::Escape
…but this gives a blank page. In fact the whole Wiki seems to be a bit
broken, with little documentation actually apparently existing and the
search engine failing to find anything at all under “URI”. Am I missing
something here?
