I understand that if I have a string in perl called "my_str" and it happens to be "Tuesday" I can test it like this:-
Code:
if ($my_str eq Tuesday) {
# do something here, because it's Tuesday !
}
But suppose I want to test for the substring "day" - so that "daytime", "Monday", "Tuesday", "Saturday" etc would all would all provide a positive match - how can I achieve that with perl 
[Footnote...] I discovered a way to achieve this using the index statement - e.g.
Code:
if (-1 != index($my_str, "day")) {
# do something
}
but I assume that'll probably be case sensitive. Case sensitivity isn't necessarily undesirable but I just wondered if there's any other function available that's more elegant / more suited to string searches?