give examples of incorrect args

doc/Language/operators.pod6

@@ -1063,10 +1063,17 @@ X<String repetition operator>.
 Coerces C<$a> to L<Str> and C<$b> to L<Int> and repeats the string C<$a> C<$b>
 times. Return the empty string if C<< $b <= 0 >>.
 
-    say 'ab' x 3;       # ababab
-    say 42 x 3;         # 424242
+    say 'ab' x 3;           # ababab
+    say 42 x 3;             # 424242
+    my $a = 'a'; my $b = 3;
+    say $a x $b;            # aaa
 
-Note there is no warning to the user when C<$b> is coerced to a zero or negative integer.
+Note there is currently no warning to the user when C<$b> is coerced to a zero or negative integer:
+
+    say 5 x ' ';            # ''
+    say 5 x 'a';            # ''
+    my $a = 3; my $b = 'a';
+    say $a x $b;            # ''
 
 =head2 infix C«xx»