Scala Collections: Why Not?
notes date: 2015-11-24
source links:
source date: 2014-01-09
Two ways to define Sets, they are complementary
+--------------------+-----------------+-------------+
| | Intensional | Extensional |
+--------------------+-----------------+-------------+
| Specification | Membership test | Members |
| Variance | Set[-A] | Set[+A] |
| Defining Signature | A => Boolean | Iterable[A] |
| Size | Unknowable | Known |
| Duplicates | Meaningless | Disallowed |
+--------------------+-----------------+-------------+