monomorphism-restriction/monomorphic-variable-and-pattern-bindings.md

+# All variable/pattern bindings are monomorphic unless a signature is given
+
+
+(one of the proposals for reforming the [MonomorphismRestriction](monomorphism-restriction))
+
+**For:**
+
+- Simpler than the M-R
+- Polymorphism in local variable bindings is rare (but less rare at the top-level), and can always be recovered with a type signature
+
+**Against:**
+
+- Against the spirit of Haskell - shouldn't compromise expressiveness for performance by default
+- Already huge potential for ruining your performance without the M-R, why introduce such draconian measures just for this?
+- Monomorphic bindings lead to hard to understand errors when polymorphism was expected
+- Haskell doesn't define an operational semantics so introducing a concept of sharing into the report would be odd.