4.9. Intersection Types
An intersection type takes the form T1 & ... & Tn (n > 0), where Ti (1 ≤ i ≤ n) are type expressions.
Intersection types arise in the processes of capture conversion (§5.1.10) and type inference (§15.12.2.7). It is not possible to write an intersection type directly as part of a program; no syntax supports this.
The values of an intersection type are those objects that are values of all of the types Ti for 1 ≤ i ≤ n.
The members of an intersection type T1 & ... & Tn are determined as follows:
• For each Ti (1 ≤ i ≤ n), let Ci be the most specific class or array type such that Ti <: Ci. Then there must be some Tk <: Ck such that Ck <: Ci for any i (1 ≤ i ≤ n), or a compile-time error occurs.
• For 1 ≤ j ≤ n, if Tj is a ...
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