MethodType constructor Null safety

1. macro_builder
2. definition
3. MethodType
4. MethodType constructor

MethodType class

1. Constructors
2. MethodType
3. Properties
4. definingClass
5. hashCode
6. isAbstract
7. isExternal
8. isGetter
9. isSetter
10. name
11. namedParameters
12. positionalParameters
13. returnType
14. runtimeType
15. typeParameters
16. Methods
17. noSuchMethod
18. toString
19. Operators
20. operator ==