Deriving Data does not work for attached code
I get the following error when I try to derive Data
for the attached code:
Main.hs:17:66:
Couldn't match expected type `Bar (D a b)'
with actual type `t' a1 b1'
Expected type: Maybe (c (Bar (D a b)))
Actual type: Maybe (c (t' a1 b1))
In the expression: gcast2 f
In an equation for `dataCast2': dataCast2 f = gcast2 f
Trac metadata
Trac field | Value |
---|---|
Version | 7.1 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | mmitar@gmail.com |
Operating system | |
Architecture |