SemigroupSum constructor

1. func_dart_core
2. integer
3. SemigroupSum
4. SemigroupSum constructor

SemigroupSum class

1. Constructors
2. SemigroupSum
3. Properties
4. hashCode
5. runtimeType
6. Methods
7. concat
8. noSuchMethod
9. toString
10. Operators
11. operator ==