Meandering sequences

[amiika]

Would be nice to have some sort of syntax for "meandering" sequences.

Syntax could be something like:

1..5~3 # Meander by 3 but keep first and last, for example: 1 3 4 2 5
1..5?3 # Meander by 3 (similar to suffle but using 3 random swaps), for example: 3 1 2 5 4

Meandering could be implemented as method ringing or on basis of cycle notation or meandric permutation.

To have more control over "meandering" it could also be implemented as list transformation using syntax similar to cycle notation:

(1 (2 3) (4 5 6) 7)<permutation>(2) # Would only permutate lists (2 3) (4 5 6) by 2