copies: show we can read data from the "first" mapping
In practice this make no difference since `t` is a copy of `a`. Having this
change before hand will make the next cleanup changeset clearer.
This is work on the road to using some native code for some performance critical
part of copy tracing.
{
// Enforcing
"eqeqeq" : true, // true: Require triple equals (===) for comparison
"forin" : true, // true: Require filtering for..in loops with obj.hasOwnProperty()
"freeze" : true, // true: prohibits overwriting prototypes of native objects such as Array, Date etc.
"nonbsp" : true, // true: Prohibit "non-breaking whitespace" characters.
"undef" : true, // true: Require all non-global variables to be declared (prevents global leaks)
// Environments
"browser" : true // Web Browser (window, document, etc)
}