If the LABEL is omitted, the loop control statement
refers to the innermost enclosing loop. This may include dynamically
looking back your call-stack at run time to find the LABEL. Such
-desperate behavior triggers a warning if you use the B<-w> flag.
+desperate behavior triggers a warning if you use the C<use warnings>
+praga or the B<-w> flag.
Unlike a C<foreach> statement, a C<while> statement never implicitly
localises any variables.