Detection of TF instance conflict depends on instance order
With 6.10 RC1, the following code compiles without complaint:
{-# OPTIONS -fglasgow-exts #-}
module OverlapTest where
type family A x
type instance A a = Bool
type instance A Int = Chareven though the overlapping instances "A a" and "A Int" conflict. Reordering the instances to
{-# OPTIONS -fglasgow-exts #-}
module OverlapTest where
type family A x
type instance A Int = Char
type instance A a = Boolcorrectly doesn't compile, complaining about conflicting instances.
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.9 |
| Type | Bug |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler (Type checker) |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | Unknown/Multiple |
| Architecture | Unknown/Multiple |