# HG changeset patch
# User nipkow
# Date 1588628086 -7200
# Node ID a86e37f4ad6056d4f4acbcabae33b01f3469b51a
# Parent  a9df6686ed0e4b0b7319168233e6b0a4a370c6f6
tuned var. names

diff -r a9df6686ed0e -r a86e37f4ad60 src/HOL/Data_Structures/AVL_Bal_Set.thy
--- a/src/HOL/Data_Structures/AVL_Bal_Set.thy	Mon May 04 16:28:39 2020 +0200
+++ b/src/HOL/Data_Structures/AVL_Bal_Set.thy	Mon May 04 23:34:46 2020 +0200
@@ -40,28 +40,28 @@
 "rot22 b = (if b=Lh then Rh else Bal)"
 
 fun balL :: "'a tree_bal change \<Rightarrow> 'a \<Rightarrow> bal \<Rightarrow> 'a tree_bal \<Rightarrow> 'a tree_bal change" where
-"balL AB' bc b C = (case AB' of
-   Same AB \<Rightarrow> Same (Node AB (bc,b) C) |
-   Diff AB \<Rightarrow> (case b of
-     Bal \<Rightarrow> Diff (Node AB (bc,Lh) C) |
-     Rh \<Rightarrow> Same (Node AB (bc,Bal) C) |
+"balL AB' c bc C = (case AB' of
+   Same AB \<Rightarrow> Same (Node AB (c,bc) C) |
+   Diff AB \<Rightarrow> (case bc of
+     Bal \<Rightarrow> Diff (Node AB (c,Lh) C) |
+     Rh \<Rightarrow> Same (Node AB (c,Bal) C) |
      Lh \<Rightarrow> Same(case AB of
-       Node A (ab,Lh) B \<Rightarrow> Node A (ab,Bal) (Node B (bc,Bal) C) |
+       Node A (ab,Lh) B \<Rightarrow> Node A (ab,Bal) (Node B (c,Bal) C) |
        Node A (ab,Rh) B \<Rightarrow> (case B of
-         Node B\<^sub>1 (bb, bB) B\<^sub>2 \<Rightarrow>
-           Node (Node A (ab,rot21 bB) B\<^sub>1) (bb,Bal) (Node B\<^sub>2 (bc,rot22 bB) C)))))"
+         Node B\<^sub>1 (b, bb) B\<^sub>2 \<Rightarrow>
+           Node (Node A (ab,rot21 bb) B\<^sub>1) (b,Bal) (Node B\<^sub>2 (c,rot22 bb) C)))))"
 
 fun balR :: "'a tree_bal \<Rightarrow> 'a \<Rightarrow> bal \<Rightarrow> 'a tree_bal change \<Rightarrow> 'a tree_bal change" where
-"balR A ab b BC' = (case BC' of
-   Same BC \<Rightarrow> Same (Node A (ab,b) BC) |
-   Diff BC \<Rightarrow> (case b of
-     Bal \<Rightarrow> Diff (Node A (ab,Rh) BC) |
-     Lh \<Rightarrow> Same (Node A (ab,Bal) BC) |
+"balR A a ba BC' = (case BC' of
+   Same BC \<Rightarrow> Same (Node A (a,ba) BC) |
+   Diff BC \<Rightarrow> (case ba of
+     Bal \<Rightarrow> Diff (Node A (a,Rh) BC) |
+     Lh \<Rightarrow> Same (Node A (a,Bal) BC) |
      Rh \<Rightarrow> Same(case BC of
-       Node B (bc,Rh) C \<Rightarrow> Node (Node A (ab,Bal) B) (bc,Bal) C |
+       Node B (bc,Rh) C \<Rightarrow> Node (Node A (a,Bal) B) (bc,Bal) C |
        Node B (bc,Lh) C \<Rightarrow> (case B of
-         Node B\<^sub>1 (bb, bB) B\<^sub>2 \<Rightarrow>
-           Node (Node A (ab,rot21 bB) B\<^sub>1) (bb,Bal) (Node B\<^sub>2 (bc,rot22 bB) C)))))"
+         Node B\<^sub>1 (b, bb) B\<^sub>2 \<Rightarrow>
+           Node (Node A (a,rot21 bb) B\<^sub>1) (b,Bal) (Node B\<^sub>2 (bc,rot22 bb) C)))))"
 
 fun insert :: "'a::linorder \<Rightarrow> 'a tree_bal \<Rightarrow> 'a tree_bal change" where
 "insert x Leaf = Diff(Node Leaf (x, Bal) Leaf)" |
diff -r a9df6686ed0e -r a86e37f4ad60 src/HOL/Data_Structures/AVL_Set_Code.thy
--- a/src/HOL/Data_Structures/AVL_Set_Code.thy	Mon May 04 16:28:39 2020 +0200
+++ b/src/HOL/Data_Structures/AVL_Set_Code.thy	Mon May 04 23:34:46 2020 +0200
@@ -26,25 +26,25 @@
 "node l a r = Node l (a, max (ht l) (ht r) + 1) r"
 
 definition balL :: "'a avl_tree \<Rightarrow> 'a \<Rightarrow> 'a avl_tree \<Rightarrow> 'a avl_tree" where
-"balL AB b C =
+"balL AB c C =
   (if ht AB = ht C + 2 then
      case AB of 
-       Node A (a, _) B \<Rightarrow>
-         if ht A \<ge> ht B then node A a (node B b C)
+       Node A (ab, _) B \<Rightarrow>
+         if ht A \<ge> ht B then node A ab (node B c C)
          else
            case B of
-             Node B\<^sub>1 (ab, _) B\<^sub>2 \<Rightarrow> node (node A a B\<^sub>1) ab (node B\<^sub>2 b C)
-   else node AB b C)"
+             Node B\<^sub>1 (b, _) B\<^sub>2 \<Rightarrow> node (node A ab B\<^sub>1) b (node B\<^sub>2 c C)
+   else node AB c C)"
 
 definition balR :: "'a avl_tree \<Rightarrow> 'a \<Rightarrow> 'a avl_tree \<Rightarrow> 'a avl_tree" where
 "balR A a BC =
    (if ht BC = ht A + 2 then
       case BC of
-        Node B (b, _) C \<Rightarrow>
-          if ht B \<le> ht C then node (node A a B) b C
+        Node B (bc, _) C \<Rightarrow>
+          if ht B \<le> ht C then node (node A a B) bc C
           else
             case B of
-              Node B\<^sub>1 (ab, _) B\<^sub>2 \<Rightarrow> node (node A a B\<^sub>1) ab (node B\<^sub>2 b C)
+              Node B\<^sub>1 (b, _) B\<^sub>2 \<Rightarrow> node (node A a B\<^sub>1) b (node B\<^sub>2 bc C)
   else node A a BC)"
 
 fun insert :: "'a::linorder \<Rightarrow> 'a avl_tree \<Rightarrow> 'a avl_tree" where