Rubyish way to invert a regular expression

Suppose a regex comes from calling code, outside of the current context, and then is passed on to another call implemented outside of the current project: ``` ["1", "2"].grep(/1/) #=> ["1"] ``` Is there a simple, Rubyish way to achieve the following behavior when the call is being made? ``` ["1", "2"].grep(/1/.negate) #=> ["2"] ``` This behavior is similar to switching the `=~` operator with the `!~` operator. It is possible to use `#select` or `#reject`, of course, or to open up or subclass `Regexp`. But I'm curious whether there is a way already available in Ruby to negate the matches returned by a regular expression in the manner above. Also, I don't care whether `false` or `nil` or `true` or the position of a match are involved in accomplishing this effect. There is a theoretical question which is relevant but which goes beyond the simple considerations here. EDIT: I get that iterators are the general way to go in Ruby for filtering a list, but people are overlooking the constraints of the question. Also, I think there is something nicely functional about the way the regex is being inverted. I don't see it as being overwrought or too-clever by half; it's plain-old object-oriented programming and the kind of thing that Ruby excels at doing.