In the above example I have an array on the LHS and an array on the RHS. This is equivalent to:
Strictly speaking... this not true. You have a list on the LHS, as per perlfaq4: What is the difference between a list and an array:
A list is a fixed collection of scalars. An array is a variable that holds a variable collection of scalars. An array can supply its collection for list operations, so list operations also work on arrays
Array operations, which change the scalars, rearranges them, or adds or subtracts some scalars, only work on arrays. These can't work on a list, which is fixed. Array operations include shift, unshift, push, pop, and splice.