global (var variable) ⇒ boolean
Promotes a local variable or parameter to a global variable. It keeps a copy of the local version as well as the global,
but produces a global copy. If the variable is not defined, that is, the variable cannot be found in the
global variables, parameters or local variables for the current function, the function returns
otherwise it returns
global function is used to push a variable to the global status. ZPE
uses what is referred to as a global function. This is a function in which all other
functions run within.
A simple call stack shows how the global function overarches everything that runs within a script.
When a variable is promoted to global it will move straight to the global function variables, even if defined in a parent first.