The pattern for split isn't terribly complicated either: 

  my @contigs = split /(?<=[^N])N++\B/, $sequence{$key};

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Update: /[^N]\KN++\B/ with a \K will also work, as long as you don't capture the gaps.

In reply to Re: Splitting only on internal pattern, not at start or end of string by oiskuu
in thread Splitting only on internal pattern, not at start or end of string by BiologySwede

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