“delete” function in Perl is mainly used to delete the given element/key, which in return deletes its associated value(s) too. So, exists() on such key would return false.
Note: Assigning undefined value to a key in has doesn’t remove its key but delete() function would do that. So, use delete() or assigning undefined value wisely.
The general syntax for delete function is:
[perl]delete EXPR
[/perl]