Elaborate a bit about my %s is SetHash

Also noting the new parameterization feature as available since 2019.01

Author: lizmat

doc/Type/SetHash.pod6

@@ -79,12 +79,37 @@ It is also possible to initialize a single key with the use of C<{}>:
     say $sh;            # OUTPUT: «SetHash(key1 key2)␤»
     say $sh.keys.perl;  # OUTPUT: «("key1", "key2").Seq␤»
 
-or, in order to initialize more than one key at the same time, use a list assignment:
+or, in order to initialize more than one key at the same time, use a list
+assignment:
 
    my $sh = SetHash.new;
    $sh{ 'a', 'b', 'c' } = True, False, True;
    say $sh.keys.perl;  # OUTPUT: «("a", "c").Seq␤»
 
+You can also create C<SetHash> masquerading as a hash by using the C<is> trait:
+
+    my %sh is SetHash = <a b c>;
+    say %sh<a>;  # True
+    say %sh<d>;  # False
+
+Since 6.d (2019.01 and later) it is also possible to specify the type of values
+you would like to allow in a C<SetHash>.  This can either be done when calling
+C<.new>:
+
+    # only allow Pairs
+    my $n = SetHash[Pair].new: "zero" => 0, "one" => 1, "two" => 2;
+
+or using the masquerading syntax:
+
+    # only allow strings
+    my %sh is SetHash[Str] = <a b c>;
+    say %sh<a>;  # True
+    say %sh<d>;  # False
+
+    # only allow whole numbers
+    my %sh is SetHash[Int] = <a b c>;
+    # Type check failed in binding; expected Int but got Str ("a")
+
 =head1 Operators
 
 Perl 6 provides common set operators, which can take C<SetHash>es (or any other
@@ -115,4 +140,4 @@ L<Sets, Bags, and Mixes|/language/setbagmix>
 
 =end pod
 
-# vim: expandtab softtabstop=4 shiftwidth=4 ft=perl6
+# vim: expandtab softtabstop=4 shiftwidth=4 ft=perl6