First part of new MAIN features refs #2632: Enumeration

Author: JJ

doc/Language/create-cli.pod6

@@ -196,6 +196,28 @@ Usage:
     --verbose                required verbosity
 =end code
 
+C<Enumeration>s can be used in signatures with arguments converted
+automatically to its corresponding C<enum> symbol:
+
+=begin code
+enum Flags  (
+    FLAG_FOO => 0b001,
+    FLAG_BAR => 0b010,
+    FLAG_BAZ => 0b100,
+);
+
+sub MAIN( Enumeration $flag = FLAG_FOO) {
+    say "Flagging $flag";
+}
+=end code
+
+This will work correctly with
+
+=for code :lang<text>
+raku MAIN-enum.p6 FLAG_BAR
+
+but will die if called with something that is not an enum.
+
 X<|%*SUB-MAIN-OPTS>
 =head2 %*SUB-MAIN-OPTS