1 - empty hashes or arrays will match.
- 2 - that is, each element matches the element of same index in the other
- array. [3]
+ 2 - that is, each element smart-matches the element of same index in the
+ other array. [3]
3 - If a circular reference is found, we fall back to referential equality.
4 - a range is written EXPR..EXPR (using the C<..> range operator, but
NOT the three-dot version C<...>, which will be treated as a boolean