Test:
PROC [] = {
im ← Create[4];
im[0][0] ← 0; im[0][1] ← 1; im[0][2] ← 1; im[0][3] ← 0;
im[1][0] ← 0; im[1][1] ← 0; im[1][2] ← 0; im[1][3] ← 1;
im[2][0] ← 0; im[2][1] ← 0; im[2][2] ← 0; im[2][3] ← 1;
im[3][0] ← 1; im[3][1] ← 0; im[3][2] ← 0; im[3][3] ← 0;
imSeq ← CreateIMSeq[im];
UpdateIMSeq[imSeq, 0];
UpdateIMSeq[imSeq, 1];
UpdateIMSeq[imSeq, 3];
UpdateIMSeq[imSeq, 0];
UpdateIMSeq[imSeq, 1];
UpdateIMSeq[imSeq, 3];
UpdateIMSeq[imSeq, 0];
UpdateIMSeq[imSeq, 1];
ERROR
};