Javascript Regex: How to find index of each subexpression?
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Suppose I have the string: `BLAH BLAH BLAH copy 2`.
I want to find the index of the two pieces, the word 'copy' and a number that may follow the word copy.

I have the regex: `/(copy)\s+([0-9]+)$/i` which successfully matches copy and 2 from the above string.  How can I find the index of the number 2? I know I can use .index to find the position of the matched test 'copy 2', but I would like to get the position of '2' so that I can increment it.