package namespace
Declares that the rest of the
innermost enclosing block, subroutine, eval
or file belongs to the indicated namespace. (The scope of a package declaration
is thus the same as the scope of a
local or my declaration.) All subsequent references to unqualified
global identifiers will be resolved by looking them up in the declared packages
symbol table. A package declaration affects
only global variables - including those you've used local on - but not
lexical variables created with my.
Typically you would put a package declaration as the first thing in a file that
is to be included by the require or use operator, but you can put one anywhere that a
statement would be legal. When defining a class or a module file, it is
customary to name the package the same name as the file, to avoid confusion.
(It's also customary to name such packages beginning with a capital letter,
because lowercase modules are, by convention, interpreted as pragmas.)