I need slices of varying length from the input array. There's currently no way to express this succintly - the splice solution is merely the least unsatisfactory given my biases. It's not good, no, but the alternative is even worse.

The other approach would have been to loop over the letter array and manually compare previous and current property. Conceptually, that's a very basic form of pattern matching - so why not use the native pattern matching mechanism Perl already offers?

The problem is that the regex engine only works against characters in a string - if it was possible to run against any ordered sequence of elements, regardless of representation (whether that be the traditional characters in a string or elements in an array or maybe something else completely like records in a database), I wouldn't need to go through mapping to a string first. Rather than get a series of strings out of the match, I'd get exactly the series of slices I'm building manually here.

Since I can only have the former, I have to somehow construct the latter from that. And a series of slice lengths to take from an array is not elegantly expressible in current Perl idioms.

Makeshifts last the longest.