Sam Stites

Polymorphic types

12 Jan 2016 - Belmont, CA

In looking up some information on Hindley-Milner, I came across this insightful point:

An expression which is in multiple sets could have zero, one, or many types. For an expression to have many types is what it means to be polymorphic. (Source)

Which may seem blatantly obvious, but when put in the context of: