zap, var1 [, var2, …] [, /pointer]
Completely removes the listed variables (except for function pointers).
Afterward, it is as if they never existed. If a (function) pointer is
zapped, then the corresponding variable, subroutine, function, or
blockroutine, and all associated variables and executable code, get
zapped. To zap a (function) pointer itself, add the
zap cannot be used inside a user-defined
subroutine or function.
See also: delete, pointer