Abstract classes in hs-boot should not be treated as injective
They could be implemented by a newtype (see mkClass
), making them non-injective.
Fortunately, this doesn't seem to cause any unsoundness, because the *constructor* for the newtype corresponding to a class is never in scope, so we are never allowed to unwrap "class newtypes". Phew!
Trac metadata
Trac field | Value |
---|---|
Version | 8.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | low |
Resolution | Unresolved |
Component | Compiler (Type checker) |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |