-
Simon Peyton Jones authored
An egregious bug in the type checker meant that it was possible for a "signature type variable" (a MetaTv of SigTv form) to be instantatiated with a type-constructor application. This destroys the invariant for SigTv. The fix is easy; adding the predicate TcType.isTyConableTyVar Fixes Trac #1153
ad17cf6e