The recurring patterns captured as a Monoid
The common patterns There are recurrent patterns, which has been captured in familiar “standard” abstractions. Monoid A Set along with a composition operation, which has an identity element. addition, for (+) identity is 0 concatenation, which is a specialization of putting together, identity is "". List, a fundamental recursive sum-type, identity is [] Option, a specialization of empty/non-empty aspect of a List, identity is None Boolean logic, very subtle, identity is False (false imply nothing) The notion that some Boolean operations form a Monoid is very subtle, but it will emerge with conditional expressions....