Adds Attribute.gist refs #2632

doc/Type/Attribute.pod6

@@ -7,10 +7,10 @@
     class Attribute { }
 
 In Perl 6 lingo, an I<attribute> refers to a per-instance/object storage slot.
-An C<Attribute> is used to talk about classes' and roles' attributes on the
+An C<Attribute> is used to talk about classes' and roles' attributes at the
 meta level.
 
-Normal usage of attributes does not require the user to use class Attribute
+Normal usage of attributes does not require the user to use this class
 explicitly.
 
 The usual way to obtain an object of type C<Attribute> is by introspection:
@@ -245,6 +245,8 @@ using L<bless|/routine/bless>.
 
 =head2 trait is rw
 
+Defined as:
+
     multi sub trait_mod:<is> (Attribute:D $attr, :$rw!)
 
 Marks an attribute as read/write as opposed to the default
@@ -262,6 +264,27 @@ writable value.
    CATCH { default { put .^name, ': ', .Str } };
    # OUTPUT: «X::Assignment::RO: Cannot modify an immutable Any␤»
 
+=head2 method gist
+
+Defined as
+
+    multi method gist(Attribute:D:)
+
+Returns the name of the type followed by the name of the attribute.
+
+=for code
+class Hero { 
+    has @!inventory;
+    has Str $.name;
+    submethod BUILD( :$name, :@inventory ) {
+        $!name = $name;
+        @!inventory = @inventory
+    }
+}
+say Hero.^attributes(:local)[0]; # OUTPUT: «Positional @!inventory»
+
+Since say implicitly calls C<.gist>, that is what produces the output here.
+
 =end pod
 
-# vim: expandtab softtabstop=4 shiftwidth=4 ft=perl6
+# vim: expandtab softtabstop=4 shiftwidth=4 ft=perl6