use autouse 'Carp' => qw(carp croak); carp "this carp was predeclared and autoused ";
Module
is already loaded, then the declaration
use autouse 'Module' => qw(func1 func2($;$) Module::func3);
is equivalent to
use Module qw(func1 func2);
if Module
defines func2()
with prototype ($;$)
, and func1()
and func3()
have no prototypes. (At
least if Module
uses Exporter
's
import, otherwise it is a fatal error.)
If the module Module
is not loaded yet, then the above declaration declares functions
func1()
and func2()
in the current package, and
declares a function Module::func3(). When these functions are called, they
load the package Module
if needed, and substitute themselves with the correct definitions.
autouse
will move important steps of your program's execution from compile time to
runtime. This can
autouse
d has some initialization which it expects to be done early.
autouse
line is wrong, you will not find it out until the corresponding function is
executed. This will be very unfortunate for functions which are not always
called (note that for such functions autouse
ing gives biggest win, for a workaround see below).
use Module; use autouse Module => qw(carp($) croak(&$)); carp "this carp was predeclared and autoused ";
The first line ensures that the errors in your argument specification are found early. When you ship your application you should comment out the first line, since it makes the second one useless.
autouse
directive and a call to Module::func3(), warnings about redefinition would
appear if warnings are enabled.
If Module::func3() is autoused, warnings are disabled when loading the module via autoused functions.
perl(1).