The isURL validator does not correctly validate http://www.

[GEMI]

If I enter "http://www.uk" the validator says that it's a valid URL, however we can clearly see that it's not. The problem is that the trailing www after the protocol is not recognized as 'www' and is treated like the beginning of the url which can be something like 'abc.uk' or similar.

[chriso]

That is a valid URL. Checking whether the TLD allows registration of that domain, or checking whether the page actually exists, is outside the scope of the library.

[GEMI]

Ok I didn't know that. Anyway for real life usage it is an invalid URL...