I’ve never actually used this function, but could definitely see using it to
help profile a system and/or to help identify defined but unused variables.
To obtain an array of all of the defined variables you would:
$defined = get_defined_vars
The function returns a multi-dimensional array of all of the defined variables.
This is not limited to used-defined variables, so you will end up seeing server
and environment variables as well.
There are also some complementary functions that allow you to get a list of the
defined functions and constants, get_defined_functions()
and
get_defined_constants()
respectively.
Have you ever used this function or know of a good use for it? Share it in the
comments below, I’d love to hear about it!