prefix-minus-resolution.md

@@ -88,6 +88,7 @@ As a further option it is possible to support multiple prefix minus application.
 
 For other examples see
 [ http://www.haskell.org/pipermail/haskell-prime/2010-July/003229.html](http://www.haskell.org/pipermail/haskell-prime/2010-July/003229.html)
+(it also shows how easy an implementation is)
 
 
 Mixfix analysis \[Aasa95\] usually only considers the top-level operators of argument terms.
@@ -100,4 +101,33 @@ Other specification languages (like HasCASL) do so, too. For instance the logica
 
 My point 3. is backed by the fact that "in case of doubt" prefix application should bind stronger than infix application.
 
-## Report Delta
\ No newline at end of file
+## Report Delta
+
+
+In
+[ http://www.haskell.org/onlinereport/haskell2010/](http://www.haskell.org/onlinereport/haskell2010/)
+
+
+remove "same precedence" stuff
+
+
+haskellch3.html\#x8-220003
+"Negation is the only prefix operator in Haskell; it has the same precedence as the infix - operator defined in the Prelude (see Section 4.4.2, Figure 4.1)."
+
+
+haskellch3.html\#x8-280003.4
+"Prefix negation has the same precedence as the infix operator - defined in the Prelude (see Table 4.1)"
+
+
+Possibly refer to haskellch10.html\#x17-17900010.6 "10.6  Fixity Resolution"
+
+
+replace:
+"The handling of the prefix negation operator, -, complicates matters only slightly. Recall that prefix negation has the same fixity as infix negation: left-associative with precedence 6. The operator to the left of -, if there is one, must have precedence lower than 6 for the expression to be legal. The negation operator itself may left-associate with operators of the same fixity (e.g. +). So for example -a + b is legal and resolves as (-a) + b, but a + -b is illegal."
+
+
+with:
+"The handling of the prefix negation operator, -, complicates matters only slightly. (Recall that) prefix negation has lower precedence than infix multiplication. The operator to the left of prefix -, if there is one, is ignored. So a + -b or a \* -b are legal. Prefix negation binds tighter with infix operators to the right of lower precedence than multiplication. So for example -a + b is legal and resolves as (-a) + b."
+
+
+(Use may algorithm from [ http://hackage.haskell.org/trac/ghc/ticket/4180](http://hackage.haskell.org/trac/ghc/ticket/4180))