Using splice to replace a subset of the top level array with an anonymous array holding the values replaced is fairly easy:

@sorted = 0 .. 9;;

splice @sorted, 1, 8, [ @sorted[ 1 .. 8 ] ];;

pp @sorted;;
(0, [1, 2, 3, 4, 5, 6, 7, 8], 9)
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However, if you need to perform that same operation on one of the nested anonymous arrays, it gets somewhat more complicated:

splice @{ $sorted[1] }, 1, 6, [ @{ $sorted[ 1] }[ 1 .. 6 ] ];;

pp @sorted;;
(0, [1, [2, 3, 4, 5, 6, 7], 8], 9)
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And if you need to go deeper still, it starts to get quite unweildy:

splice @{ $sorted[1][1] }, 1, 4, [ @{ $sorted[1][1] }[ 1 .. 4 ] ];;

pp @sorted;;
(0, [1, [2, [3, 4, 5, 6], 7], 8], 9)
[download]