Poor error message for Coercible constraint unsatisfiability
If I say
import Data.Coerce
foo = coerce
I get
Couldn't match representation of type ‘a0’ with that of ‘b0’
‘a0’ is untouchable
inside the constraints: ()
bound by the inferred type of foo :: a0 -> b0
at /Users/rae/temp/bug/App.hs:3:1-12
Relevant bindings include
foo :: a0 -> b0 (bound at /Users/rae/temp/bug/App.hs:3:1)
In the expression: coerce
In an equation for ‘foo’: foo = coerce
How awful. Eta-expanding foo
works fine, though.
Trac metadata
Trac field | Value |
---|---|
Version | 7.11 |
Type | Bug |
TypeOfFailure | OtherFailure |
Priority | normal |
Resolution | Unresolved |
Component | Compiler |
Test case | |
Differential revisions | |
BlockedBy | |
Related | |
Blocking | |
CC | |
Operating system | |
Architecture |