Just a really quick attempt. Obviously not quite the same as var_dump in PHP…
But for the “object - dump” you’ve asked for, and if with “contents” you’ve meant the properties, then it might just be enough (depends on what you want/need to “see”). And one can always do even more if needed… 
Somehow the Xojo IDE populates the Debugger-infos - I don’t know how, but I could imagine it’s doing that using Introspection…
…but maybe we get another “uh, no” for that assumption from @Norman Palardy 