Perl Question - make sure array has unique strings only

I need to build a list (array) of urls in string form. Im going to incrementally add urls to the list as i crawl the web and find new urls to add. My question is how can i ensure that each time I am aobut to add a new url to the list, that it is not already in the list?

The only way i can think of, is to loop through the list before each add to make sure the newly found url is not already in there, but this must be really inefficient, especially since i expect my list to grow to 10000 in size or perhaps more.


Is there a better way to keep track of the urls ive alreay visited and avoid visiting them again?

i don't actually know perl, but do you know if perl has an inarray function of some type? something where you can compair a string to all elements of an array.

thats basically what you need to do