I went down this same track, and came up with a version that doesn't munge $_:

s/(\d)/$s+=$1,$1/ge;

[download]
Although I was hampered by the fact that this doesn't work in psh for some reason.

Alan

In reply to Re: Requiring backtracking a certain number of times by ferrency
in thread Requiring backtracking a certain number of times by dragonchild

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