Maybe the best way to do it, to avoid clobberage, would be to make a hash of arrays?

So that for instance,

name => "john", 
age => "25", 
supervisor => "john", 
job => "programmer", 
location => "US"
[download]

would become

john => ['name','supervisor'], 
25  => ['age'], 
programmer  => ['job'], 
us => ['location']
[download]

that way, if any of your arrays had two or more elements, you'd know something had got clobbered...