16. • (gradual typing)
– (dynamic typing) (static typing)
– Jeremy G. Siek and Walid Taha, Gradual Typing for Functional Languages, in
Proceedings of the 2006 Scheme and Functional Programming Workshop
•
– dynamic type: Any … Any
– type consistency relation: A B
• A = B Any
( : int→Any Any→str)
–
int ⊑ Any ⊑ str
•
(1)