In Selenium IDE, how to get the value of the base url

Is it possible to retrieve the value of the base url from inside a Selenium script (a plain HTML-saved script from Selenium IDE)? What I'm trying to do is verify the current url using `assertLocation`. But `assertLocation` returns the absolute url. I would like to compare the current url to a relative url without having to use an `*` at the start of the url. I'd like to have access to the base string because I want to be able to run the tests on different sites (various dev sites + production site), but if I use the `*` I can not check for the root page (`*/` would be true for each page that ends with a `/`...) This is what I currently do: |assertLocation | */some-page | | This is what I'd like to do: |assertLocation | baseURL + "/some-page" | | Note: is it even possible to: - use a variable in the target; - concatenate a variable and a string?