Provide examples that demonstrate repeat statement always runs once

Author: skids

doc/Language/control.pod6

@@ -671,21 +671,41 @@ is evaluated at the end of the loop, even if it appears at the front.
     } while $x < 5;
     $x.say; # 5
 
+    repeat {
+        $x++;
+    } while $x < 5;
+    $x.say; # 6
+
     repeat while $x < 10 {
         $x++;
     }
     $x.say; # 10
 
+    repeat while $x < 10 {
+        $x++;
+    }
+    $x.say; # 11
+
     repeat {
         $x++;
     } until $x >= 15;
     $x.say; # 15
 
+    repeat {
+        $x++;
+    } until $x >= 15;
+    $x.say; # 16
+
     repeat until $x >= 20 {
         $x++;
     }
     $x.say; # 20
 
+    repeat until $x >= 20 {
+        $x++;
+    }
+    $x.say; # 21
+
 All these forms may produce a return value the same way C<loop> does.
 
 =head1 X<return|control flow>