I'm working on a program where I'm dealing with long strings that look like this (only much longer): 0000010000000100000100001. I want to fill in the area between the 1s with zeros, so that string would become 0000011111111100000111111. I know that I can match the zeros with m/(?<=1)0+(?=1)/, but I don't know how to go about replacing all of the 0s with 1s just inside the match. Can I chain that with tr// somehow?

In reply to Creating a fill-in regexp by jpfarmer

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