Changes between Version 386 and Version 387 of TypeFunctionsStatus
- Oct 2, 2008 4:58:50 AM (7 years ago)
v386 v387 20 20 21 21 * Constraint simplification: 22 * #2448 (givens not properly used in superclass entailment check) 23 22 * #2102 (superclass equalities) 24 23 * To fix superclass equalities (specifically getting the coercion evidence), we could introduce a kind of typelet just for evidence. In fact, re-use `HsBind.VarBind` and make its right-hand side a specially data structure describing evidence construction, instead of being a general `HsExpr`. That evidence construction generation can have a case for extracting superclass constraints. The desugarer than has to generate the case expression bringing the equality in scope from that.