I am having trouble translating this into Ruby.
Here is a piece of JavaScript that does exactly what I want to do:
function get_code(str){
return str
If you need to use a regex to filter some results, and THEN use only the capture group, you can do the following:
str = "Leesburg, Virginia 20176"
state_regex = Regexp.new(/,\s*([A-Za-z]{2,})\s*\d{5,}/)
# looks for the comma, possible whitespace, captures alpha,
# looks for possible whitespace, looks for zip
> str[state_regex]
=> ", Virginia 20176"
> str[state_regex, 1] # use the capture group
=> "Virginia"