...but not that simple regexp. He didn't indicate that there was only one delimiter in the string.

my @entries = $longstring =~ /(.*?)(?:<!--NEWENTRY(\d+)-->)/g;
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This will interleave the data with the numbers from the delimiter.

Update: Thanks to kvale for pointing out that this drops trailing data. I cannot come up with a foolproof fix using only a pattern match capture. This one will keep all data, but will tack on a phantom (empty) delimiter entry if the line ends with data:

my @entries = $longstring =~ /(.*?)(?:<!--NEWENTRY(\d+)-->|$)/g;
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