In fact, the files behind the link are nothing but such an offline copy ...
If you use the"Web Version" icon right to the "Download Documentation" icon you see the "real" Web-Version that enables searches and the realtime excecution of sample programs. If the community convinces someone to set up an 7.40 AS ABAP offering that http-service (https://host:port/sap/public/bc/abap/docu) publicly, you would gain access to a real online version.
Just dreamin'