defaulting.md

@@ -234,3 +234,32 @@ Concrete proposal:  a default decl can occur anywhere that a type signature woul
 ### Cons
 
 - Changes the Haskell'98 behaviour (where defaults are module-local).  Question: Do any real programs actually rely on the Haskell'98 spec here?
+
+## Proposal 4 - remove defaulting
+
+
+It is generally agreed that defaulting, in its current form at least, is a wart on the language. The main motivation behind it is to make simple calculator-like uses of interactive Haskell environments possible.
+
+
+This proposal, then, is to remove defaulting from the language; we would expect that interactive environments will continue to default as they think best. Note that implementations already go beyond what is stated in the report when defaulting.
+
+
+Most(?) instances of defaulting in Real Programs are due to (\^). If this proposal is adopted then we would recommend changing the type of (\^) and introducing genericPower (or some better name) thus:
+
+```wiki
+(^)          :: (Num a) => a -> Int -> a
+genericPower :: (Num a, Integral b) => a -> b -> a
+```
+
+
+This is similar to the scheme used by, for example, genericIndex.
+
+### Pros
+
+- Easy to implement and explain.
+- Makes the language smaller.
+- Trivially fixes any problems tools like hat have with defaulting.
+
+### Cons
+
+- No pretense at trying to remain compatible with Haskell '98, but how many uses of defaulting are there in the wild? And how many not covered by (\^)?