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This is an excerpt from the latest version perlfaq7.pod, which
comes with the standard Perl distribution. These postings aim to
reduce the number of repeated questions as well as allow the community
to review and update the answers. The latest version of the complete
perlfaq is at .


7.5: How do I temporarily block warnings?

If you are running Perl 5.6.0 or better, the "use warnings" pragma
allows fine control of what warning are produced. See perllexwarn for
more details.

no warnings; # temporarily turn off warnings
$a = $b + $c; # I know these might be undef

Additionally, you can enable and disable categories of warnings. You
turn off the categories you want to ignore and you can still get other
categories of warnings. See perllexwarn for the complete details,
including the category names and hierarchy.

no warnings 'uninitialized';
$a = $b + $c;

If you have an older version of Perl, the $^W variable (documented in
perlvar) controls runtime warnings for a block:

local $^W = 0; # temporarily turn off warnings
$a = $b + $c; # I know these might be undef

Note that like all the punctuation variables, you cannot currently use
my() on $^W, only local().


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