options

        # Regexp.options

(from ruby core)
---
    rxp.options   -> integer

---

Returns the set of bits corresponding to the options used when creating
this Regexp (see Regexp::new for details. Note that additional bits may
be set in the returned options: these are used internally by the regular
expression code. These extra bits are ignored if the options are passed
to Regexp::new.

    Regexp::IGNORECASE                  #=> 1
    Regexp::EXTENDED                    #=> 2
    Regexp::MULTILINE                   #=> 4

    /cat/.options                       #=> 0
    /cat/ix.options                     #=> 3
    Regexp.new('cat', true).options     #=> 1
    /\xa1\xa2/e.options                 #=> 16

    r = /cat/ix
    Regexp.new(r.source, r.options)     #=> /cat/ix