diff --git a/plantuml/gilded-rose.puml b/plantuml/gilded-rose.puml
index 7c463967..63f3c7a5 100644
--- a/plantuml/gilded-rose.puml
+++ b/plantuml/gilded-rose.puml
@@ -9,25 +9,25 @@ end note
 if (not "Aged Brie" and not "Backstage passes to a TAFKAL80ETC concert") then (yes)
     if (quality > 0) then (yes)
         if (not "Sulfuras, Hand of Ragnaros") then (yes)
-            -lower quality with 1
+            :lower quality with 1;
         else (no)
         endif
     else (no)
     endif
 else (no)
     if (quality < 50) then (yes)
-        -increase quality with 1
+        :increase quality with 1;
         if ("Backstage passes to a TAFKAL80ETC concert") then (yes)
             if (sell in < 11) then (yes)
                 if (quality < 50) then (yes)
-                    -increase quality with 1
+                    :increase quality with 1;
                 else (no)
                 endif
             else (no)
             endif
             if (sell in < 6) then (yes)
                 if (quality < 50) then (yes)
-                    -increase quality with 1
+                    :increase quality with 1;
                 else (no)
                 endif
             else (no)
@@ -39,7 +39,7 @@ else (no)
 endif
 
 if (not "Sulfuras, Hand of Ragnaros") then (yes)
-    -lower sell in with 1
+    :lower sell in with 1;
 else (no)
 endif
 
@@ -48,17 +48,17 @@ if (sell in < 0) then (yes)
         if (not "Backstage passes to a TAFKAL80ETC concert") then (yes)
             if (quality > 0) then (yes)
                 if (not "Sulfuras, Hand of Ragnaros") then (yes)
-                    -lower quality with 1
+                    :lower quality with 1;
                 else (no)
                 endif
             else (no)
             endif
         else (no)
-            -lower quality with quality
+            :lower quality with quality;
         endif
     else (no)
         if (quality < 50) then (yes)
-            -increase quality with 1
+            :increase quality with 1;
         else (no)
         endif
     endif
diff --git a/plantuml/history/01_lower-both-values.puml b/plantuml/history/01_lower-both-values.puml
index 35715abe..151691a5 100644
--- a/plantuml/history/01_lower-both-values.puml
+++ b/plantuml/history/01_lower-both-values.puml
@@ -6,9 +6,8 @@ note left
     An item has a name, a sell in value and a quality value
 end note
 
--lower quality with 1
-
--lower sell in with 1
+:lower quality with 1;
+:lower sell in with 1;
 
 stop
 
diff --git a/plantuml/history/02_sell-by-passed.puml b/plantuml/history/02_sell-by-passed.puml
index 730f7e5f..71d8559a 100644
--- a/plantuml/history/02_sell-by-passed.puml
+++ b/plantuml/history/02_sell-by-passed.puml
@@ -6,11 +6,11 @@ note left
     An item has a name, a sell in value and a quality value
 end note
 
--lower quality with 1
--lower sell in with 1
+:lower quality with 1;
+:lower sell in with 1;
 
 if (sell in < 0) then (yes)
-    -lower quality with 1
+    :lower quality with 1;
 else (no)
 endif
 
diff --git a/plantuml/history/03_quality-never-negative.puml b/plantuml/history/03_quality-never-negative.puml
index 18cee44a..a0965397 100644
--- a/plantuml/history/03_quality-never-negative.puml
+++ b/plantuml/history/03_quality-never-negative.puml
@@ -7,15 +7,15 @@ note left
 end note
 
 if (quality > 0) then (yes)
-    -lower quality with 1
+    :lower quality with 1;
 else (no)
 endif
 
--lower sell in with 1
+:lower sell in with 1;
 
 if (sell in < 0) then (yes)
     if (quality > 0) then (yes)
-        -lower quality with 1
+        :lower quality with 1;
     else (no)
     endif
 else (no)
diff --git a/plantuml/history/04_aged-brie.puml b/plantuml/history/04_aged-brie.puml
index ac495227..7bdf78b9 100644
--- a/plantuml/history/04_aged-brie.puml
+++ b/plantuml/history/04_aged-brie.puml
@@ -8,23 +8,23 @@ end note
 
 if (not "Aged Brie") then (yes)
     if (quality > 0) then (yes)
-        -lower quality with 1
+        :lower quality with 1;
     else (no)
     endif
 else (no)
-    -increase quality with 1
+    :increase quality with 1;
 endif
 
--lower sell in with 1
+:lower sell in with 1;
 
 if (sell in < 0) then (yes)
     if (not "Aged Brie") then (yes)
         if (quality > 0) then (yes)
-            -lower quality with 1
+            :lower quality with 1;
     else (no)
         endif
     else (no)
-        -increase quality with 1
+        :increase quality with 1;
     endif
 else (no)
 endif
diff --git a/plantuml/history/05_quality-max-50.puml b/plantuml/history/05_quality-max-50.puml
index 6991f51b..c76615b9 100644
--- a/plantuml/history/05_quality-max-50.puml
+++ b/plantuml/history/05_quality-max-50.puml
@@ -8,27 +8,27 @@ end note
 
 if (not "Aged Brie") then (yes)
     if (quality > 0) then (yes)
-        -lower quality with 1
+        :lower quality with 1;
     else (no)
     endif
 else (no)
     if (quality < 50) then (yes)
-        -increase quality with 1
+        :increase quality with 1;
     else (no)
     endif
 endif
 
--lower sell in with 1
+:lower sell in with 1;
 
 if (sell in < 0) then (yes)
     if (not "Aged Brie") then (yes)
         if (quality > 0) then (yes)
-            -lower quality with 1
+            :lower quality with 1;
         else (no)
         endif
     else (no)
         if (quality < 50) then (yes)
-            -increase quality with 1
+            :increase quality with 1;
         else (no)
         endif
     endif
diff --git a/plantuml/history/06_sulfuras.puml b/plantuml/history/06_sulfuras.puml
index 1690228c..b464e40d 100644
--- a/plantuml/history/06_sulfuras.puml
+++ b/plantuml/history/06_sulfuras.puml
@@ -9,20 +9,20 @@ end note
 if (not "Aged Brie") then (yes)
     if (quality > 0) then (yes)
         if (not "Sulfuras, Hand of Ragnaros") then (yes)
-            -lower quality with 1
+            :lower quality with 1;
         else (no)
         endif
     else (no)
     endif
 else (no)
     if (quality < 50) then (yes)
-        -increase quality with 1
+        :increase quality with 1;
     else (no)
     endif
 endif
 
 if (not "Sulfuras, Hand of Ragnaros") then (yes)
-    -lower sell in with 1
+    :lower sell in with 1;
 else (no)
 endif
 
@@ -30,14 +30,14 @@ if (sell in < 0) then (yes)
     if (not "Aged Brie") then (yes)
         if (quality > 0) then (yes)
             if (not "Sulfuras, Hand of Ragnaros") then (yes)
-                -lower quality with 1
+                :lower quality with 1;
             else (no)
             endif
         else (no)
         endif
     else (no)
         if (quality < 50) then (yes)
-            -increase quality with 1
+            :increase quality with 1;
         else (no)
         endif
     endif
diff --git a/plantuml/history/07_backstage-passes.puml b/plantuml/history/07_backstage-passes.puml
index 7c463967..63f3c7a5 100644
--- a/plantuml/history/07_backstage-passes.puml
+++ b/plantuml/history/07_backstage-passes.puml
@@ -9,25 +9,25 @@ end note
 if (not "Aged Brie" and not "Backstage passes to a TAFKAL80ETC concert") then (yes)
     if (quality > 0) then (yes)
         if (not "Sulfuras, Hand of Ragnaros") then (yes)
-            -lower quality with 1
+            :lower quality with 1;
         else (no)
         endif
     else (no)
     endif
 else (no)
     if (quality < 50) then (yes)
-        -increase quality with 1
+        :increase quality with 1;
         if ("Backstage passes to a TAFKAL80ETC concert") then (yes)
             if (sell in < 11) then (yes)
                 if (quality < 50) then (yes)
-                    -increase quality with 1
+                    :increase quality with 1;
                 else (no)
                 endif
             else (no)
             endif
             if (sell in < 6) then (yes)
                 if (quality < 50) then (yes)
-                    -increase quality with 1
+                    :increase quality with 1;
                 else (no)
                 endif
             else (no)
@@ -39,7 +39,7 @@ else (no)
 endif
 
 if (not "Sulfuras, Hand of Ragnaros") then (yes)
-    -lower sell in with 1
+    :lower sell in with 1;
 else (no)
 endif
 
@@ -48,17 +48,17 @@ if (sell in < 0) then (yes)
         if (not "Backstage passes to a TAFKAL80ETC concert") then (yes)
             if (quality > 0) then (yes)
                 if (not "Sulfuras, Hand of Ragnaros") then (yes)
-                    -lower quality with 1
+                    :lower quality with 1;
                 else (no)
                 endif
             else (no)
             endif
         else (no)
-            -lower quality with quality
+            :lower quality with quality;
         endif
     else (no)
         if (quality < 50) then (yes)
-            -increase quality with 1
+            :increase quality with 1;
         else (no)
         endif
     endif