FAQ 7.5 How do I temporarily block warnings?

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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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