Final decision about enum new syntax (specification)

spec-docs/enums.md

@@ -37,28 +37,28 @@ Issues
     * Option 1.1: Forbid short annotation syntax in enums. **downside**: cannot annotate functions/properties/classes in this enum
     * Option 1.2: Add a separator between enum constants and members, and forbid short annotation syntax only on enum entriesc themselves. **downside**: separator is not intuitive, hard to think of when doing this for the first time (the error message will be rather clear and instructive, though)
     * Option 1.3: prefix each entry with a soft-keyword, e.g. `entry`. **downside**: verbosity
+    * Option 1.4 **chosen**: Add a semicolon separator after the last enum constant, **and** a comma separator between different enum constants.
 * How do we specify other supertypes for a constant (if any)
-    * Option 2.1: Leave unsupported, use cases are very few, and Java does not support it
+    * Option 2.1 **chosen**: Leave unsupported, use cases are very few, and Java does not support it
     * Option 2.2: `A("s"): OtherType`
 
-Example for option 1.2:
+Example for option 1.4:
 
 ``` kotlin
 enum class Foo(val s: String) {
-    A("a") // semicolon CAN NOT be used here!
-    B("b")
+    A("a"), // semicolon CAN NOT be used here!
+    B("b"), // comma is MANDATORY after each enum constant except the last one
     C("c") {
         override fun foo() { ... }
-    }; // semicolon is MANDATORY here, if a member follows
+    }; // semicolon is MANDATORY here, even if no member follows
   
-    // if no semicolon was provided, `open` is another enum entry
     open fun foo() {}
 }
 ```
 
 Notes:
-* No overhead in the most common case of no members at all: `enum class E {A B C}
-* Clear error message: if the parser sees a member, but no semicolon before it:
-    * it reports an error saying "There must be a semicolon separating enum entries from members", which is rather instructive
+* Almost no overhead in the most common case of no members at all: `enum class E {A, B, C; }
+* Clear error message: if the parser sees no semicolon after the last constant:
+    * it reports an error saying "There must be a semicolon after the last enum entry", which is rather instructive
     * a quick fix can even guess the right position for the semicolon most of the time
 * Today, there's no way of naming an enum entry `public` (or any other soft-keyword used as a modifier), which is unfortunate