Ruby dynamic syntax checking

From the file sample/test.rb in the Ruby source code distribution:

def valid_syntax?(code, fname)
eval("BEGIN {return true}\n#{code}", nil, fname, 0)
rescue Exception
puts $!.message
false
end

original post: http://groups.google.com/group/comp.lang.ruby/browse_thread/thread/1efc85a01ab278f4?pli=1