lawbreakers in Text.PrettyPrint.HughesPJ

[Christian Maeder]

Christian Maeder wrote:
> @@ -607,8 +611,13 @@

Myline number may be wrong, because I used an older version of the 
module. After the introduction of above_ and beside_ it also makes sense 
to move the call of reduceDoc to the last argument (and remove this 
calls in reduceDoc and above). The patch for this is below. I cannot 
observe speed differences, though.

Christian

@@ -461,8 +461,8 @@
  type RDoc = Doc

  reduceDoc :: Doc -> RDoc
-reduceDoc (Beside p g q) = beside p g (reduceDoc q)
-reduceDoc (Above  p g q) = above  p g (reduceDoc q)
+reduceDoc (Beside p g q) = beside p g q
+reduceDoc (Above  p g q) = above  p g q
  reduceDoc p              = p


@@ -562,15 +562,15 @@
  above_ :: Doc -> Bool -> Doc -> Doc
  above_ Empty _ q = q
  above_ p _ Empty = p
-above_ p g q = Above p g q
+above_ p g q = Above p g (reduceDoc q)

  p $$  q = above_ p False q
  p $+$ q = above_ p True q

  above :: Doc -> Bool -> RDoc -> RDoc
  above (Above p g1 q1)  g2 q2 = above p g1 (above q1 g2 q2)
-above p@(Beside _ _ _) g  q  = aboveNest (reduceDoc p) g 0 (reduceDoc q)
-above p g q                  = aboveNest p             g 0 (reduceDoc q)
+above p@(Beside _ _ _) g  q  = aboveNest (reduceDoc p) g 0 q
+above p g q                  = aboveNest p             g 0 q

  aboveNest :: RDoc -> Bool -> Int -> RDoc -> RDoc
  -- Specfication: aboveNest p g k q = p $g$ (nest k q)
@@ -614,7 +614,7 @@
  beside_ :: Doc -> Bool -> Doc -> Doc
  beside_ Empty _ q = q
  beside_ p _ Empty = p
-beside_ p g q = Beside p g q
+beside_ p g q = Beside p g (reduceDoc q)

  p <>  q = beside_ p False q
  p <+> q = beside_ p True  q