ns_absoluteurl - Construct a completed URL from an incomplete URL based on a base URL
Construct a completed URL from a incomplete (e.g. relative) URL by taking as many parts as possible from the provided base URL. The function uses internally ns_parseurl for parsing the provided URLs into its components.
% ns_absoluteurl foo.html http://openacs.org//projects/openacs/download/
http://openacs.org//projects/openacs/download/foo.html
% ns_absoluteurl foo.html {http://[::1]:80/t.html}
http://[::1]:80/foo.html
% ns_absoluteurl //google.com/ https://openacs.org/forums
https://google.com/