What is the point of replace function in Memcache?

Question

What is the point of replace function in PHP memcache if you can just use set? Even if there is a variable, set automatically replaces it, right?

Can you give me an example where it's better to use replace instead of set?

Thanks.

Answer 1

According to PHP.net:

Memcached::replace() is similar to Memcached::set(), but the operation fails if the key does not exist on the server.