Type Alias InterfaceVtables 

pub type InterfaceVtables = FxHashMap<(StructId, InterfaceId), Vec<(StructId, Spur)>>;

Vtable witnesses keyed by (struct_id, interface_id). The value is the conforming type’s method-key list in interface declaration order; codegen looks each one up in the function map to build the vtable global.

Aliased Type

pub struct InterfaceVtables { /* private fields */ }