if (!(indexValue instanceof IntValue)) {
Util.abort(value, "subscript " + index + " is not an integer: " + indexValue);
}
Vector vector1 = (Vector) vector;
int i = ((IntValue) indexValue).value;
if (i >= 0 && i < vector1.size()) {
vector1.set(i, v);
} else {
Util.abort(this, "subscript out of bound: " + i + " v.s. [0, " + (vector1.size() - 1) + "]");
}
}