2D array in Postscript

Question

How are 2D arrays created in postscript?

I'm thinking that I need an array where every element is an array, the array in this case is called shape.

/shape 2 array def
/shape_length 3 def
shape 0 2 array put
shape 1 2 array put
shape 2 2 array put

% [[null, null, null], [null, null, null], [null, null, null]]

I could create a loop instead of copying a line 3 times like this.

I may not otherwise need shape_length.

Is this a good way to go about doing this or is there something more succinct?

Answer 1

The creation of such a structure can indeed be done very concisely:

[3{3 array}repeat]

Using Ghostscript interactively, you can see that it actually results in the desired array:

GS>[3{3 array}repeat]==
[[null null null] [null null null] [null null null]]