Conceptually similar to Go, which was also similarly copied for C++. Instead of being hierarchical, however, which introduces complexity into len, is_empty, etc. - though we might only want those for testing by GA - this uses a Cow to copy the HashMap only when necessary.
Conceptually similar to Go, which was also similarly copied for C++. Instead of being hierarchical, however, which introduces complexity into
len,is_empty, etc. - though we might only want those for testing by GA - this uses aCowto copy theHashMaponly when necessary.Closes #1655