Simplify given `Coercible` constraints
It would be feasible and possibly useful if
foo :: Coercible [a] [b] => a -> b
foo = coerce
would work. This involve simplifying CtGivens similar to how given (nominal) equalities are simplified.
I’ll defer working on this, as it is not strictly required, it seems.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.7 |
| Type | FeatureRequest |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler (Type checker) |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | #8503 (closed) |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |