Support empty record update syntax
Empty record update syntax would be useful for when you are changing phantom type parameters. It is currently explicitly disallowed, but it isn't clear if that is absolutely necessary to me.
data R phantom = C { a,b :: Int }
r :: R Int
r = C 1 2
--This is OK
r1 :: R Char
r1 = r { a = a r }
--Why not this?
r2 :: R Char
r2 = r {}
Trac metadata
Trac field | Value |
---|---|
Version | 7.6.2 |
Type | FeatureRequest |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |