--> Access the real property:
bool(true)
%unicode|string%(15) "object property"

--> Remove the real property and access the array element:
bool(true)
%unicode|string%(13) "array element"

--> Remove the array element and try access again:
bool(false)

Notice: Undefined index:  p in %s on line %d
NULL

--> Re-add the real property:
bool(true)
%unicode|string%(15) "object property"