warnings(3) Perl Programmers Reference Guide warnings(3)NAMEwarnings - Perl pragma to control optional warningsSYNOPSIS
use warnings;
no warnings;
use warnings "all";
no warnings "all";
use warnings::register;
if (warnings::enabled()) {
warnings::warn("some warning");
}
if (warnings::enabled("void")) {
warnings::warn("void", "some warning");
}
if (warnings::enabled($object)) {
warnings::warn($object, "some warning");
}
warnif("some warning");
warnif("void", "some warning");
warnif($object, "some warning");
DESCRIPTION
If no import list is supplied, all possible warnings are
either enabled or disabled.
A number of functions are provided to assist module
authors.
use warnings::register
Creates a new warnings category with the same name as
the package where the call to the pragma is used.
warnings::enabled()
Use the warnings category with the same name as the
current package.
Return TRUE if that warnings category is enabled in
the calling module. Otherwise returns FALSE.
warnings::enabled($category)
Return TRUE if the warnings category, "$category", is
enabled in the calling module. Otherwise returns
FALSE.
warnings::enabled($object)
Use the name of the class for the object reference,
"$object", as the warnings category.
Return TRUE if that warnings category is enabled in
the first scope where the object is used. Otherwise
returns FALSE.
warnings::warn($message)
Print "$message" to STDERR.
Use the warnings category with the same name as the
current package.
If that warnings category has been set to "FATAL" in
the calling module then die. Otherwise return.
warnings::warn($category, $message)
Print "$message" to STDERR.
If the warnings category, "$category", has been set to
"FATAL" in the calling module then die. Otherwise
return.
warnings::warn($object, $message)
Print "$message" to STDERR.
Use the name of the class for the object reference,
"$object", as the warnings category.
If that warnings category has been set to "FATAL" in
the scope where "$object" is first used then die. Oth
erwise return.
warnings::warnif($message)
Equivalent to:
if (warnings::enabled())
{ warnings::warn($message) }
warnings::warnif($category, $message)
Equivalent to:
if (warnings::enabled($category))
{ warnings::warn($category, $message) }
warnings::warnif($object, $message)
Equivalent to:
if (warnings::enabled($object))
{ warnings::warn($object, $message) }
See the Pragmatic Modules entry in the perlmodlib manpage
and the perllexwarn manpage.
2001-02-22 perl v5.6.1 warnings(3)