semver.md: added the prerelease and metadata fields

semver.md

@@ -392,6 +392,50 @@ flowchart TB
   end
   DASH3["-"]
 
+  subgraph "PRERELEASE"
+    direction LR
+    PRERELEASESTART{{"prerelease"}}
+    subgraph "PRERELEASE1"
+        PRERELEASE1START{{"Choose one"}}
+        ZERO4A["'0'"]
+        ONETONINE4A["'1'-'9'"]
+        DIGIT4A["digit"]
+
+        DIGIT4B["digit"]
+        LETTER4B["'a'-'z' or 'A'-'Z' or '-'"]
+        CHAR4B["'0'-'9' or 'a'-'z' or 'A'-'Z' or '-'"]
+        PRERELEASE1END{{"END part 1"}}
+    end
+    DOT4A["."]
+    subgraph "PRERELEASE2"
+        PRERELEASE2START{{"Choose one"}}
+        ZERO4C["'0'"]
+        ONETONINE4C["'1'-'9'"]
+        DIGIT4C["digit"]
+
+        DIGIT4D["digit"]
+        LETTER4D["'a'-'z' or 'A'-'Z' or '-'"]
+        CHAR4D["'0'-'9' or 'a'-'z' or 'A'-'Z' or '-'"]
+        PRERELEASE2END{{"END part 2"}}
+    end
+
+    PRERELEASEEND{{END prerelease}}
+  end
+
+  PLUS4["+"]
+
+  subgraph BUILDMETADATA
+    direction LR
+    BUILDMETADATASTART{{"START"}}
+    CHAR5A["'0'-'9' or 'a'-'z' or 'A'-'Z' or '-'"]
+    DOT5["."]
+    CHAR5B["'0'-'9' or 'a'-'z' or 'A'-'Z' or '-'"]
+    BUILDMETADATAEND{{"END"}}
+
+  end
+
+  ENDOFLINE{{"End of line"}}
+
   START --> MAJOR
   ONETONINE1 --> DIGIT1
   MAJORSTART --> ONETONINE1
@@ -424,6 +468,59 @@ flowchart TB
   ONETONINE3 --> PATCHEND
 
   PATCH --> DASH3
+  DASH3 --> PRERELEASE
+
+  PRERELEASE1 --> DOT4A
+
+  PRERELEASESTART --> PRERELEASE1
+  PRERELEASE1START --> ZERO4A
+  PRERELEASE1START --> ONETONINE4A
+  PRERELEASE1START --> DIGIT4B
+  ONETONINE4A --> DIGIT4A
+  ONETONINE4A --> PRERELEASE1END
+  DIGIT4A --> PRERELEASE1END
+  DIGIT4A --> DIGIT4A
+  DIGIT4B --> LETTER4B
+  DIGIT4B --> DIGIT4B
+  LETTER4B --> CHAR4B
+  LETTER4B --> PRERELEASE1END
+  CHAR4B --> PRERELEASE1END
+  ZERO4A --> PRERELEASE1END
+
+  DOT4A --> PRERELEASE2
+
+  PRERELEASE2START --> ZERO4C
+  PRERELEASE2START --> ONETONINE4C
+  PRERELEASE2START --> DIGIT4D
+  ONETONINE4C --> DIGIT4C
+  ONETONINE4C --> PRERELEASE2END
+  DIGIT4C --> PRERELEASE2END
+  DIGIT4C --> DIGIT4C
+  DIGIT4D --> LETTER4D
+  DIGIT4D --> DIGIT4D
+  LETTER4D --> CHAR4D
+  LETTER4D --> PRERELEASE2END
+  CHAR4D --> PRERELEASE2END
+  ZERO4C --> PRERELEASE2END
+
+  PRERELEASE2 --> PRERELEASEEND
+
+  PRERELEASE --> PLUS4
+
+  PLUS4 --> BUILDMETADATA
+
+  BUILDMETADATASTART --> CHAR5A
+  CHAR5A --> CHAR5A
+  CHAR5A --> DOT5
+  CHAR5A --> BUILDMETADATAEND
+  DOT5 --> CHAR5B
+  CHAR5B -->CHAR5B
+  CHAR5B --> DOT5
+  CHAR5B --> BUILDMETADATAEND
+
+  DASH3 --> ENDOFLINE
+  PLUS4 --> ENDOFLINE
+  BUILDMETADATA --> ENDOFLINE
 ```
 
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