Implement cursor_fresh and mixin

lib/Cursor.cs

@@ -407,6 +407,10 @@ public Cursor(Cursor parent, string method, int from, int to)
         return new Cursor(global, mo, nstate, xact, npos, null);
     }
 
+    public Cursor FreshClass(IP6 from) {
+        return new Cursor(global, from.mo, nstate, xact, pos, null);
+    }
+
     public Cursor StripCaps() {
         return new Cursor(global, save_klass, from, pos, null);
     }

src/CgOp.pm

@@ -214,6 +214,7 @@ use warnings;
     sub cursor_O       { rawcall($_[0], 'O:m,Variable', $_[1]) }
     sub cursor_synthetic { rawnew('cursor', @_[0,1,2,3]) }
     sub cursor_synthcap{ rawcall($_[0], 'SynPushCapture:m,Void', @_[1,2]) }
+    sub cursor_fresh   { rawcall($_[0], 'FreshClass:m,Cursor', $_[1]) }
     sub rxstripcaps    { rawcall($_[0], 'StripCaps:m,Cursor') }
 
     sub fcclist_new    { rawnewarr('cc', @_) }

v6/tryfile

@@ -1,6 +1,8 @@
 # vim: ft=perl6
 use MONKEY_TYPING;
 
+#use STD;
+
 sub infix:<min>($a,$b) { $a > $b ?? $b !! $a }
 
 augment class Cursor {
@@ -57,4 +59,10 @@ augment class Cursor {
     }
 
     method deb($str) { note $str }
+
+    method cursor_fresh($k = self) { Q:CgOp {
+        (ns (cursor_fresh (cast cursor (@ {self})) (@ {$k})))
+    } }
+
+    method mixin($role) { self.cursor_fresh(self.WHAT but $role) }
 }