The PUSH method of VPGL Language add an element of top of the array.
PUSH takes 2 inputs or 1 input with option, emits 1 output. PUSH starts on both input arriving if it has no option, or starts on arriving an object through input 0 with option. In both case input 0 is an array, input 1 or option is the element to be added on top of the array. PUSH append the element at the top of the array, then emits this result array to ouput 0.