Array.pip()

Array.pip(SomePathIndexArray, SomeLength, SomePassThroughFunction,UseClone)

pip is push plus insert. The array is split at the nodes in SomePathIndexArray, and a slice of length SomeLength is pushed into these array indices, and the values are massaged with SomePassThroughFunction if provided.
pip modifies the original array, unless UseClone is true.
SomePathIndexArray is array indices to refer to a specific cell in the array to be pip-ed.

Example: 1..10.pip(5,2)

1

2

3

4

5

6 7

8

9

10

MAGICSQUARE(3).pip([1,1],2).print()

[ [2,7,6 ],

[9, [5,1 ] ],

[4,3,8 ] ]

MAGICSQUARE(3).pip([1,1],2,x=>SUM(x)).print()

[ [2,7,6 ],

[9,6 ],

[4,3,8 ] ]