can newtype be extended to permit GADT-like declarations
I'd like to create the following value constructor without the overhead of data:
data B n e x where
B :: Body n -> B n C CHowever, if I ask for newtype instead of data I'm told that a newtype constructor must have a return type of form T a1 ... an. Is this restriction fundamental? If not, could it be possible to allow GADT-like declarations for newtype?
Trac metadata
| Trac field | Value |
|---|---|
| Version | 6.12.1 |
| Type | FeatureRequest |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Compiler (Type checker) |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |